The opinion of the court was delivered by

Schroeder, J.:

This is an action for malpractice against a hospital and the physician in charge of its radiology department to recover for injuries sustained as the result of radiation therapy with radioactive cobalt, alleged to have been given in an excessive amount.

The plaintiff (appellant), Irma Natanson, suffering from a cancer of the breast, had a radical left mastectomy performed on May 29, 1955. At the direction of Dr. Crump acker, the surgeon who performed that operation, the plaintiff engaged Dr. John R. Kline, a radiologist, for radiation therapy to the site of the mastectomy and the surrounding areas.

Dr. Kline, a licensed physician and specialist in radiation therapy, was head of the radiology department at St. Francis Hospital at Wichita, Kansas. The plaintiff seeks damages for injuries claimed to have been sustained as a result of alleged acts of. negligence in the administration of the cobalt radiation treatment. Dr. Kline and the hospital were named as defendants (appellees).

The case was tried to a jury which returned a verdict in favor of both defendants. The plaintiff’s motion for a new trijal having been denied, this appeal followed specifying various trial) errors.

The questions controlling the decision herein relate to the giving of instructions by the trial court. )

It will be unnecessary to relate in detail all the facts presented by the evidence as abstracted, consisting of more than three hWdred pages, to dispose of the issues on appeal. ¡

The jury was submitted two special questions. In the? first it found that the defendants were not guilty of any act or j acts of negligence which were the proximate cause of plaintiff/ injury. *395 The jury having found in the negative on the first, the second question required no answer.

It must be conceded, insofar as the evidence is concerned, that all presumptions are, and must be, in favor of the verdict. All issues of fact have been resolved in favor of the defendants. (Lord v. Hercules Powder Co., 161 Kan. 268, 167 P. 2d 299; and Beye v. Andres, 179 Kan. 502, 296 P. 2d 1049.)

The appellant contends, however, the uncontradicted evidence shows the defendants negligent as a matter of law.

Dr. Kline was called by the plaintiff to testify in the trial court and in great detail counsel examined Dr. Kline to educate the court and jury concerning cobalt radiation therapy in the treatment of cancer. A short summary in rough will serve as a basis for further discussion.

The purpose of any irradiation therapy is to destroy tissue. The theory of destruction of cancer by irradiation therapy is that when treatment is given in a series of doses (fractionation in medical terms), the greater ability of normal tissue to recover from irradiation effects enables it to survive while the cancerous tissue is destroyed.

Dosages of irradiation are expressed in roentgen. All forms of irradiation have some point of maximum, or one hundred per cent, dosage and diminish as they penetrate deeper into the body. In the case of X rays the point of maximum dosage is in the skin. In the case of cobalt irradiation the maximum dosage is received at a point about five millimeters beneath the outer surface of the skin. The primary advantages of cobalt irradiation over X ray irradiation are deeper penetration and less skin injury. The amount of X ray which can be administered is governed in a large measure by the amount which the skin can tolerate. The amount of cobalt irradiation which can be administered is governed by the tolerance of the tissues lying five millimeters below the outer surface of the skin.

By “equilibrium” dose in relation to radioactive cobalt is meant the maximum dose, which occurs about five millimeters below the outer surface of the skin. “Tumor” dose means the quantity received at the known or assumed depth of the tumor.

Dr. Kline ordered the administration of cobalt irradiation for the appellant in “routine fashion.” To him and to his assistant, Dr. Somers, this meant a tumor dose of 4,400 roentgen delivered to the supraclavicular area in a period of sixteen days. For this purpose *396 the tumor was assumed to extend from outer surface in front to outer surface behind. “Routine fashion” also meant a dosage of 4,800 roentgen delivered over the outer two centimeters of the remainder of the left chest from a point at the rear portion of the left side of the patient’s body around past the breast bone in a period of twenty-three days. It also meant an approximately equal dosage to the outer two centimeters over the breast bone including the chain of lymph nodes running longitudinally along each side of the breast bone.

Material to further discussion is the fact that the prescription or outline of treatment called for 4,800 roentgen to be delivered to the outer two centimeters of the chest wall. It also directed that this treatment be delivered by means of a rotating beam. According to the testimony of the appellant’s husband the rotational equipment had not been installed and ready for use at the time of the appellant’s first treatment. It was installed and ready for use soon thereafter.

A radiologist, who administers cobalt irradiation treatment with rotational equipment, must have the assistance of a specialist in physics. Dr. Kline’s assistant was a hospital employee by the name of Darter who determined by necessary computations how to administer the desired quantity of radiation, ordered by Dr. Kline, by means of a moving beam. Darter had graduated from Wichita University with a B. S. degree the preceding spring and had a six months’ special course on irradiation therapy at Massachusetts Institute of Technology. His actual experience with radioactive cobalt therapy began with the installation of the unit at the St. Francis Hospital on January 29, 1955, some four months before the appellant’s treatment began.

Highly summarized, the evidence upon which the appellant relies is that the radioactive cobalt beam was delivered at an angle to the chest wall in an effort to avoid injury to the lungs. In making the calculations to achieve the tumor doses (one and one-half to two centimeters deep), the equilibrium doses (five millimeters deep) were not calculated by Darter.

Dr. Paul A. Roys, an assistant professor of physics at Wichita University, who was a specialist in the field of nuclear physics of which radiation physics is a part, was called to testify concerning his calculations of the roentgen delivered to various parts of the appellant’s chest wall in accordance with the time chart and dosages *397 administered to the appellant as a result of Darter’s calculations. From Dr. Roys’ calculations the equilibrium doses administered at several segments of the chest wall were from 5,670 roentgen to 6,260 roentgen at a depth of five millimeters. It was in these segments where the appellant’s injuries were sustained.

Dr. Kline had previously testified that the soft tissues of the chest wall could tolerate about 5,000 roentgen in twenty-four or twenty-five days; that the cartilage could tolerate about 5,500 roentgen over a period of twenty-eight days, and ordinarily bone would stand a larger amount. The appellant argues the effect upon her of the administration of amounts ranging from 5,670 roentgen to 6,280 roentgen certainly corroborates Dr. Kline’s testimony. The entire chest, skin, cartilage and bone were completely destroyed in those areas.

There was other evidence which contradicted the appellant’s theory, however. When Dr. Kline was called as a witness on his own behalf, he stated the prescribed dosage of 4,400 roentgen was intended as a minimum dosage, and was the smallest dosage which would be effective and had to be given, even though he knew that portions of the chest would receive a much higher dosage. He testified that a doctor has to take a chance in the treatment of cancer, that he knew there was danger of injury from such treatment, but that he took a calculated risk. This risk is determined to a large extent by the tolerance of the individual concerned. Some patients have a much higher tolerance than others. He further testified that he had treated approximately seventy-five breast and cancer cases since the treatment of the appellant, all of which were treated in the same manner with the same number of roentgens directed to be given.

Dr. Hare, a radiologist from Los Angeles, was called to testify for the appellees. He said that for five years he had been using 6,000 roentgen up to 9,000 roentgen on the treatment of cancer cases.

At the time treatment started the appellant had an ulcer about the size of a quarter under her left arm which remained from the mastectomy. It had not stopped draining. After treatment started the drainage increased and, according to the appellant, she understood the treatment was to shrink the area but instead it seemed to be growing larger.

There is no issue presented by the record as to the relationship *398 between Dr. Kline and the St. Francis Hospital. The petition pleaded that the defendants were engaged in a joint adventure or in the alternative that the defendant physician was acting within the scope of his employment as agent, servant and employee of the defendant hospital. The answer of the defendant hospital admitted that the defendant physician “was in charge of its radiology department.” Moreover, the pleadings raised no issues between the defendants.

Upon the foregoing evidence on the state of the record presented herein, it cannot be said the appellees were guilty of negligence as a matter of law. At best it may be said, upon all the facts and circumstances presented by the record, there was evidence from which a jury could find that the proximate cause of the appellant’s injury was the negligence of the defendants. On the other hand a jury, properly instructed, would be justified in finding for the appellees.

We shall next consider whether the jury was properly instructed.

The code of civil procedure requires the court to give general instructions to the jury, with or without request having been made for the same. (G. S. 1949, 60-2909, Fifth.) This provision has frequently been interpreted to require the court to define the issues and state at least generally the law applicable thereto. (Bushey v. Coffman, 109 Kan. 652, 201 Pac. 1103; Knox v. Barnard, 181 Kan. 943, 317 P. 2d 452; and Schmid v. Eslick, 181 Kan. 997, 317 P. 2d 459.) The trial court in summarizing the pleadings for the jury in its instructions was quite brief. Aside from general factual recitations the material portions of this summarization given in instruction No. 1 are as follows:

“In this case the plaintiff Irma Natanson . . . alleges . . . that Dr. Kline and personnel of St. Francis Hospital administered to the plaintiff a series of cobalt radiation treatments in such a negligent manner that the skin, flesh and muscles beneath her left arm sloughed away and ribs of her left chest were so burned that they became necrotic, or dead; . . .

“The defendants then filed their answers in the case in which they allege that the treatments were properly administered and that they were not guilty of any negligence toward the plaintiff.” (Emphasis added.)

Then followed the usual instruction (No. 2) that the foregoing statement taken from the pleadings set forth the various claims and contentions of the parties against each other, and that such claims and contentions are to be considered only as they may have been proved by evidence presented during the trial of the case.

*399 Instruction No. 3 reads in part:

“This is a lawsuit based upon negligence. In the conduct of human affairs, the law imposes upon us the obligation to use due and proper care to avoid hurt or injury to others. Thus, negligence may be defined as a violation of the duty to use due and proper care. The term, ‘due and proper care’ means, in this case, such care as medical specialists in radiology in this community would ordinarily and reasonably use under the same or similar circumstances.”

The court then instructed that negligence is never presumed — it must be proved by a preponderance or greater weight of the evidence; it defined preponderance or greater weight of the evidence and instructed that negligence may be established by circumstantial evidence.

Instruction No. 4 given by the court reads:

“The law does not require that treatments given by a physician to a patient shall attain nearly perfect results. He is not responsible in damages for lack of success or honest mistakes or errors of judgment unless it be shown that he did not possess that degree of learning and skill ordinarily possessed by radiologists of good standing in his community, or that he was not exercising reasonable and ordinary care in applying such skill and learning to the treatment of the patient. And if among radiologists more than one method of treatment is recognized, it would not be negligence for the physician to have adopted any of such methods if tire method he did adopt was a recognized and approved method in the profession at the time and place of treatment.”

On this appeal the court is not concerned with the general instructions on negligence or instruction No. 4, which correctly states the law. The cases upon which the appellees rely to substantiate these instructions are sound law. (Erastus Tefft v. Hardin H. Wilcox, 6 Kan. 46; Sly v. Powell, 87 Kan. 142, 123 Pac. 881; Paulich v. Nipple, 104 Kan. 801, 180 Pac. 771; James v. Grigsby, 114 Kan. 627, 220 Pac. 267; Riggs v. Gouldner, 150 Kan. 727, 96 P. 2d 694; Cummins v. Donley, 173 Kan. 463, 249 P. 2d 695; and Goheen v. Graber, 181 Kan. 107, 309 P. 2d 636.)

The amended petition pleaded negligence in eight specific particulars, one or more of which presented issues which the jury was required to determine on the basis of the evidence presented. It was proper for the trial court to exclude those specific allegations of negligence enumerated in the amended petition concerning which there was no evidence, but it should have set forth those specific allegations of negligence concerning which there was evidence. The general summarization, consisting of the italicized *400 portion of instruction No. 1 heretofore quoted, was insufficient to meet this obligation of the trial court.

The answers filed by both of the defendants in the lower court denied the specific allegations of negligence alleged in the amended petition and pleaded “the plaintiff assumed the risk and hazard of said treatment.”

One of the alleged grounds of negligence, concerning which there was evidence before the jury, was that Dr. Kline failed to warn the appellant the course of treatment which he undertook to administer involved great risk of bodily injury or death.

The appellant requested and the trial court refused to give the following instruction:

“You are instructed that the relationship between physician and patient is a fiduciary one. The relationship requires the physician to make a full disclosure to the patient of all matters within his knowledge affecting the interests of the patient. Included within the matters which the physician must advise the patient are the nature of the proposed treatment and any hazards of the proposed treatment which are known to the physician. Every adult person has the right to determine for himself or herself whether or not he will subject his body to hazards of any particular medical treatment.

‘You are instructed that if you find from the evidence that defendant Kline knew that the treatment he proposed to administer to plaintiff involved hazard or danger he was under a duty to advise plaintiff of that fact and if you further find that defendant Kline did not advise plaintiff of such hazards then defendant Kline was guilty of negligence.”

There was evidence from which the jury could have found that the appellant fully appreciated the danger and the risk of the radiation treatment. The appellant’s husband testified:

“Q. Yes, how did it happen you went there for the conference with Dr. Kline?

“A. We, of course, made a periodic visit to Dr. Crumpacker after the operation, and he told us that as a precautionary measure Mrs. Natanson should go to the St. Francis Hospital and take tire cobalt treatment. He explained to us that the cobalt was a new therapy; that it was much more powerful than the x-ray they had used previously. He suggested we sec Dr. Kline.”

On cross examination he testified:

“Q. Just a question or two. Mr. Natanson, when you and your wife went. to see Dr. Crumpacker, did you have a discussion with him about the purpose of the irradiation?

' “A. Yes.

“Q. And, was the general objection of irradiation explained to you?

“A. Yes.

*401 “Q. And, that was when Mis. Natanson was with you?

“A. Yes.

“Q. Now, did you consult any radiologist other than Dr. Kline in determining anything about this irradiation?

“A. No, sir.

“Q. Now, I take it that it was Dr. Crumpacker’s thought or suggestion at least to you that Dr. Kline be consulted?

“A. Yes.

“Q. And, up to the time you engaged Dr. Kline, Dr. Crumpacker had been the doctor on the case?

“A. Yes.”

There was also testimony from the appellant and her husband that Dr. Kline did not inform the appellant the treatment involved any danger whatever. The testimony of Dr. Kline, a radiologist with special training in cobalt irradiation, was that he knew he was “taking a chance” with the treatment he proposed to administer and that such treatment involved a “calculated risk.” He testified there was always a danger of injury in the treatment of cancer. Insofar as the record discloses Dr. Kline did not testify that he informed the appellant the treatment involved any danger. His only testimony relevant thereto was the following:

“Q. Now, tell us what transpired when you first met with the Natansons?

“A. I could not completely recall that meeting. It was such a long time ago.

“Q. Just tell us what you can recall of it?

“A. I remember Mr. and Mrs. Natanson coming in to see me. I can’t remember if I met them in my office or whether we were downstairs. I remember in a very vague way. I remember in a vague way that we discussed the treatment, about how long it took, the number of areas we would irradiate. I have a recollection of that. I remember we took her into the treatment room. She was marked out, measured. I believe the marking out and measurement was done by Mr. Darter. Her first treatment occurred the first day she came. I am not sure of that but I think so.

“Q. Have you told us everything you recall?

“A. Yes.”

No other evidence appears in the record concerning the subject.

The appellees argue that we are here concerned with a case where the patient consented to the treatment, but afterwards alleges that the nature and consequences of the risks of the treatment were not properly explained to her. They point out this is not an action for assault and battery, where a patient has given no consent to the treatment.

What appears to distinguish the case of the unauthorized surgery *402 or treatment from traditional assault and battery cases is the fact that in almost all of the cases the physician is acting in relatively good faith for the benefit of the patient. While it is true that in some cases the results are not in fact beneficial to a patient, the courts have repeatedly stated that doctors are not insurers. The traditional assault and battery involves a defendant who is acting for the most part out of malice or in a manner generally considered as “antisocial.” One who commits an assault and battery is not seeking to confer any benefit upon the one assaulted.

The fundamental distinction between assault and battery on the one hand, and negligence such as would constitute malpractice, on the other, is that the former is intentional and the latter unintentional. (Hershey v. Peake, 115 Kan. 562, 223 Pac. 1113; and Maddox v. Neptune, 175 Kan. 465, 264 P. 2d 1073.)

We are here concerned with a case where the patient consented to the treatment, but alleges in a malpractice action that the nature and consequences of the risks of the treatment were not properly explained to her. This relates directly to the question whether the physician has obtained the informed consent of the patient to render the treatment administered.

The treatment of a cancer patient with radioactive cobalt is relatively new. Until the use of atomic energy appeared in this country, X ray was the type of radiation treatment used for such patients. Radioactive cobalt is manufactured by the Atomic Energy Commission in a neutron pill by bombarding the stable element of cobalt in its pure state. This makes the cobalt unstable and by reason thereof it is radioactive. The radioactive cobalt emits two homogeneous beams of pure energy called gamma rays, very close in character, which are far more powerful than the ordinary X rays. It produces no other rays to be filtered out. This makes it desirable for use in the treatment of cancer patients. The cobalt machine may be compared to a three million volt X ray machine.

Radioactive cobalt is so powerful that the Atomic Energy Commission specifies the construction of the room in which the cobalt unit is to be placed. The walls of the room are made of concrete forty inches thick and the ceiling, also concrete, is twenty-four inches thick. The room is sunken down in a courtyard outside the hospital. A passageway off the control room about ten feet long leads to the treatment room. All controls are placed in the outer control room and, when the radiation treatment is administered to a patient, the *403 operator in the outer room looks through a specially designed thick lead quartz glass which gives a telescopic view. A periodic report of radiation outside the room must be made to the Atomic Energy Commission in accordance with regulations. These facts were given by Dr. Kline in his testimony.

These facts are not commonly known and a patient cannot be expected to know the hazards or the danger of radiation from radioactive cobalt unless the patient is informed by a radiologist who knows the dangers of injury from cobalt irradiation. While Dr. Kline did not testify that the radiation he gave the appellant caused her injury, he did state cobalt irradiation could cause the injury which the appellant did sustain.

What is the extent of a physician’s duty to confide in his patient where the physician suggests or recommends a particular method of treatment? What duty is there upon him to explain the nature and probable consequences of that treatment to the patient? To what extent should he disclose the existence and nature of the risks inherent in the treatment?

We have been cited to no Kansas cases, nor has our research disclosed any, dealing directly with the foregoing questions. A recent article by William A. Kelly published in the Kansas Law Review entitled “The Physician, The Patient, And The Consent” (8 Kan. L. Rev. 405), reviews many malpractice cases dealing with the consent of the patient, but the article fails to deal with the problem of disclosure involving on one hand the right of the patient to decide for himself and on the other a possible therapeutic ground for withholding information which may create tension by depressing or exciting the patient. This subject has been touched upon in an article by Charles C. Lund, M. D., “The Doctor, The Patient, And The Truth” (19 Tenn. L. Rev. 344 [1946]), and in an article by Hubert Winston Smith, LL. B., M. D., “Therapeutic Privilege To Withhold Specific Diagnosis From Patient Sick With Serious Or Fatal Illness” (19 Tenn. L. Rev. 349 [1946]). Allan H. McCoid, Associate Professor of Law, University of Minnesota, has written two recent articles, one “A Reappraisal Of Liability For Unauthorized Medical Treatment” (41 Minn. L. Rev. 381), published in March, 1957, and the other “The Care Required Of Medical Practitioners” (12 Vanderbilt L. Rev. 549, 586), published in June, 1959.

The courts frequently state that the relation between the physi *404 cían and his patient is a fiduciary one, and therefore the physician has an obligation to make a full and frank disclosure to the patient of all pertinent facts related to his illness. We are here concerned with a case where the physician is charged with treating the patient without consent on tihe ground the patient was not fully informed of the nature of the treatment or its consequences, and, therefore, any “consent” obtained was ineffective. An effort will be made to review the cases from foreign jurisdictions most nearly in point with the question presently at hand, although none may be said to be directly in point.

In 1958 the Supreme Court of Minnesota in Bang v. Charles T. Miller Hospital, 251 Minn. 427, 88 N. W. 2d 186, had an assault case before it, and though not alleged as a malpractice action for negligence, a new trial was granted on the ground that a fact issue was presented for the jury to determine whether the patient consented to the performance of the operation. There the patient went to a urologist because of urinary trouble and apparently consented to a cystoscopic examination and a prostate operation. He was not informed that part of the procedure of a transurethral prostatic resection would be the tying off of his sperm ducts. In the opinion the court said:

“While we have no desire to hamper the medical profession in the outstanding progress it has made and continues to make in connection with the study and solution of health and disease problems, it is our opinion that a reasonable rule is that, where a physician or surgeon can ascertain in advance of an operation alternative situations and no immediate emergency exists, a patient should be informed of the alternative possibilities and given a chance to decide before the doctor proceeds with the operation. By that we mean that, in a situation such as the case before us where no immediate emergency exists, a patient should be informed before the operation that if his spermatic cords were severed it would result in his sterilization, but on the other hand if this were not done there would be a possibility of an infection which could result in serious consequences. Under such conditions the patient would at least have the opportunity of deciding whether he wanted to take the chance of a possible infection if the operation was performed in one manner or to become sterile if performed in another.” (pp. 434, 435.)

A malpractice action was before the Fifth Circuit Court in Lester v. Aetna Casualty & Surety Company, 240 F. 2d 676. The patient was given electro-shock treatments prescribed by a psychiatrist and suffered a bad result. In affirming the jury’s finding the *405 court held the patient’s wife gave sufficient legal consent, and said:

“The basic, the fundamental, difficulty which confronts plaintiff on this appeal is that he presents his case as though it were one of a person being deprived by another of due process of law, instead of grounding it upon the well settled principles that a physician must, except in real and serious emergencies, acquaint the patient or, when the circumstances require it, some one properly acting for him, of the diagnosis and the treatment proposed, and obtain consent, thereto express or implied, and, consent obtained must proceed in accordance with proper reasonable medical standards and in the exercise of due care . . .” (p. 679.) (Emphasis added.)

The appellees rely upon the Canadian case of Kenny v. Lockwood [1932], 1 D. L. R. 507, where a patient alleged the defendants falsely and recklessly, without caring whether it was true or false, and without reasonable ground for believing it to be true, represented the operation to be “simple,” and that her hand “would be all right in three weeks.” No evidence was presented to suggest fraud or recklessness and the plaintiff’s argument proceeded mainly upon the duty which it was said the defendants owed to the plaintiff, due to the peculiar relation set up between a surgeon and his patient. The Ontario trial judge concluded that it was the duty of the defendant doctors to “enlighten the patient’s mind in a plain and reasonable way as to what her ailment was, as to what were the risks of operating promptly, what were the risks of delaying the operation, and what the risks of not operating at all. Having discharged that duty, it was their further duty to secure from the patient a decision or consent as to what course is to be followed, and if that decision or consent is not had and the surgeons operate and the operation turns out badly the surgeons are liable. Such a relationship is established between a person of special skill and knowledge and a person of no skill or knowledge upon the facts required for the making of a decision that, unless the person with the special skill and knowledge discharges the duty which he owes of placing the patient in a position to make a decision, that person, when he is employed and paid because of his special skill and knowledge, has failed to perform his duty, and that breach of duty makes him liable in damages for untoward results.” (Kenny v. Lockwood Clinic Ltd. [1931], 4 D. L. R. 906, 907.)

The trial court found for the plaintiff but on appeal the judgment was reversed, the appellate court saying there was some testimony *406 that the doctors had explained all details to the plaintiff, although the extracts contained in the opinion indicate that the doctor admitted to having said that the operation was not a very serious one and that he had not clearly presented the alternatives to the plaintiff. In the courts opinion it was said:

. . the duty cast upon the surgeon was to deal honestly with the patient as to the necessity, character and importance of the operation and its probable consequences and whether success might reasonably be expected to ameliorate or remove the trouble, but that such duty does not extend to warning the patient of the dangers incident to, or possible in, any operation, nor to details calculated to frighten or distress the patient.” (p. 525.)

The court concluded upon the evidence presented:

“That the defendant Stoddart reasonably fulfilled the duty laid upon him arising out of the relationship of surgeon and patient, not being guilty of ‘negligence in word’ or ‘economy of truth’ nor of misleading the plaintiff, and so is not liable for breach of the duty . . .” (p.526.)

In the opinion it was said the duty of a surgeon is to be honest in fact and to express his honest belief, and if he does so he ought not to be judged as if he had warranted a perfect cure nor to be found derelict in his duty on any meticulous criticism of his language.

The conclusion to be drawn from the foregoing cases is that where the physician or surgeon has affirmatively misrepresented the nature of the operation or has failed to point out the probable consequences of the course of treatment, he may be subjected to a claim of unauthorized treatment. But this does not mean that a doctor is under an obligation to describe in detail all of the possible consequences of treatment. It might be argued, as indicated by the authors of the various law review articles heretofore cited, that to make a complete disclosure of all facts, diagnoses and alternatives or possibilities which may occur to the doctor could so alarm the patient that it would, in fact, constitute bad medical practice. There is probably a privilege, on therapeutic grounds, to withhold the specific diagnosis where the disclosure of cancer or some other dread disease would seriously jeopardize the recovery of an unstable, temperamental or severely depressed patient. But in the ordinary case there would appear to be no such warrant for suppressing facts and the physician should make a substantial disclosure to the patient prior to the treatment or risk liability in tort.

Anglo-American law starts with the premise of thorough-going self determination. It follows that each man is considered to be master of his own body, and he may, if he be of sound mind, ex *407 pressly prohibit the performance of life-saving surgery, or other medical treatment. A doctor might well believe that an operation or form of treatment is desirable or necessary but the law does not permit him to substitute his own judgment for that of the patient by any form of artifice or deception.

The mean between the two extremes of absolute silence on the part of the physician relative to the treatment of a patient and exhaustive discussion by the physician explaining in detail all possible risks and dangers was well stated by the California District Court of Appeal in Salgo v. Leland Stanford, Etc. Bd. Trustees [1957], 154 Cal. App. 2d 560, 317 P. 2d 170. There the court had before it a malpractice action wherein the defendants were charged with negligence. The patient, his wife and son testified that the patient was not informed anything in the nature of an aortography was to be performed. Two of the doctors contradicted this, although admitting that the details of the procedure involving injection of a radio-opaque substance into the aorta and the possible dangers therefrom were not explained. As a result of the aortography the patient was paralyzed from the waist down. The trial court gave a rather broad instruction on the duty of the physician to disclose to the patient “all the facts which mutually affect his rights and interests and of the surgical risk, hazard and danger, if any.” (p. 578.) On appeal, the instruction was held to be overly broad, the court stating:

“. . . A physician violates his duty to his patient and subjects himself to liability if he withholds any facts which are necessary to form the basis of an intelligent consent by the patient to the proposed treatment. Likewise the physician may not minimize the known dangers of a procedure or operation in order to induce his patient’s consent. At the same time, the physician must place the welfare of his patient above all else and this very fact places him in a position in which he sometimes must choose between two alternative courses of action. One is to explain to the patient every risk attendant upon any surgical procedure or operation, no matter how remote; this may well result in alarming a patient who is already unduly apprehensive and who may as a result refuse to undertake surgery in which there is in fact minimal risk; it may also result in actually increasing the risks by reason of the physiological results of the apprehension itself. The other is to recognize that each patient presents a separate problem, that the patient’s mental and emotional condition is important and in certain cases may be crucial, and that in discussing the element of risk a certain amount of discretion must be employed consistent with the full disclosure of facts necessary to an informed consent . . .

“The instruction given should be modified to inform the jury that the physician has such discretion consistent, of course, with the full disclosure of facts necessary to an informed consent.” (p. 578.)

*408 The appellees rely upon Hunt v. Bradshaw [1955], 242 N. C. 517, 88 S. E. 2d 762, a North Carolina case. This was a malpractice action against a physician wherein the patient sought damages alleged to have resulted from the negligent failure of the defendant (1) to use reasonable care and diligence in the application of his knowledge and skill as a physician and surgeon, and (2) to exercise his best judgment in attempting to remove a small piece of steel from plaintiff’s body. On these allegations of negligence the plaintiff contended, among other things, that the defendant advised the plaintiff the operation was simple, whereas it was serious and involved undisclosed risks. The plaintiff’s evidence was sufficient to justify a finding the operation was of a very serious nature. The court after reviewing the evidence said:

“. . . Upon Dr. Bradshaw’s advice the operation was decided upon. It is understandable the.surgeon wanted to reassure the patient so that he would not go to the operating room unduly apprehensive. Failure to explain the risks involved, therefore, may be considered a mistake on the part of the surgeon, but under the facts cannot be deemed such want of ordinary care as to import liability.

“Proof of what is in accord with approved surgical procedure and what constitutes the standard of care required of the surgeon in performing an operation, like the advisability of the operation itself, are matters not within the knowledge of lay witnesses but must be established by the testimony of qualified experts . . .

“Plaintiff’s expert testimony is sufficient to justify the finding the injury and damage to plaintiff’s hand and arm resulted from the operation. But, as in cases of ordinary negligence, the fact that injury results is not proof the act which caused it was a negligent act. The doctrine res ipsa loquitur does not apply in cases of this character . . .

“Of course, it seems hard to the patient in apparent good health that he should be advised to undergo an operation, and upon regaining consciousness finds that he has lost the use of an arm for the remainder of his life. Infallibility in human beings is not attainable. The law recognizes, and we think properly so, that the surgeon’s hand, with its skill and training, is, after all, a human hand, guided by a human brain in a procedure in which the margin between safety and danger sometimes measures little more than the thickness of a sheet of paper,

“The plaintiff’s case fails because of lack of expert testimony that the defendant failed, either to exercise due care in the operation, or to use his best judgment in advising it . . .” (pp. 523, 524.) (Emphasis added.)

Under the facts presented by the case it does not appear the allegations of negligence were sufficient to encompass the failure of the physician to inform the patient of the risks.

An X ray case upon which the appellees rely is Costa v. Regents *409 of Univ. of California, 116 Cal. App. 2d 445, 254 P. 2d 85. This was a malpractice action against a hospital and certain doctors for alleged negligence in the X ray treatment of cancer to the area of the lower jaw which resulted in necrosis of tissue. It was alleged the X ray treatment was too drastic and extensive. While the circumstances were in many respects similar to the case at bar, it did not involve any failure of the physicians to disclose the risks. It was claimed a less drastic and extensive treatment should have been undertaken by the doctors. The court said:

“. . . The expert evidence showed clearly that the exact extent of the cancer under the surface and the absence of hidden involvements cannot in a case like appellant’s be decided with such certainty that it can be safely relied on for the purpose of restricting the treatment within narrow limits. There was no expert evidence whatever that on the data available to defendants they ought in good practice to have restricted the X-ray treatment to a less drastic procedure or that the diagnostic methods now indicated by appellant if used would have yielded certainty and should have led to restriction to less dangerous treatment. Several experts testified that said methods (X-ray pictures and biopsy) could not be relied on for the purpose. In fighting so dangerous a condition as here involved, physicians may take serious risks and in doing so must rely on their judgment in deciding how far to go. See Callahan v. Hahnemann Hospital, 1 Cal. 2d 447 [35 P. 2d 536]. To hold them responsible in the cases where the bad chance unfortunately materializes would be evidently unjust and most dangerous if physicians were deterred from going to the extent which gives their patient the best chance of survival.” (p. 457.)

The Costa case has nothing to do with the duty to inform the patient of the hazardous character of proposed treatment. The more recent case of the same court in Salgo v. Leland Stanford, Etc. Bd. Trustees, supra, covers the subject specifically.

In our opinion the proper rule of law to determine whether a patient has given an intelligent consent to a proposed form of treatment by a physician was stated and applied in Salgo v. Leland Stanford, Etc. Bd. Trustees, supra. This rule in effect compels disclosure by the physician in order to assure that an informed consent of the patient is obtained. The duty of the physician to disclose, however, is limited to those disclosures which a reasonable medical practitioner would make under the same or similar circumstances. How the physician may best discharge his obligation to the patient in this difficult situation involves primarily a question of medical judgment. So long as the disclosure is sufficient to assure an informed consent, the physicians choice of plausible courses should not be called into question if it appears, all circumstances con *410 sidered, that the physician was motivated only by the patient’s best therapeutic interests and he proceeded as competent medical men would have done in a similar situation.

Turning now to the facts in the instant case, the appellant knew she had a cancerous tumor in her left breast which was removed by a radical mastectomy. Pathological examination of the tissue removed did not disclose any spread of the cancer cells into the lymphatics beyond the cancerous tumor itself. As a precautionary measure the appellant’s ovaries and fallopian tubes were removed, which likewise upon pathological examination indicated no spread of the cancer to these organs. At the time the appellant went to Dr. Kline as a patient there was no immediate emergency concerning the administration of cobalt irradiation treatment such as would excuse the physician from making a reasonable disclosure to the patient. We think upon all the facts and circumstances here presented Dr. Kline was obligated to make a reasonable disclosure to the appellant of the nature and probable consequences of the suggested or recommended cobalt irradiation treatment, and he was also obligated to make a reasonable disclosure of the dangers within his knowledge which were incident to, or possible in, the treatment he proposed to administer.

Upon the record here presented Dr. Kline made no disclosures to the appellant whatever. He was silent. This is not to say that the facts compel a verdict for the appellant. Under the rule heretofore stated, where the patient fully appreciates the danger involved, the failure of a physician in his duty to make a reasonable disclosure to the patient would have no causal relation to the injury. In such event the consent of the patient to the proposed treatment is an informed consent. The burden of proof rests throughout the trial of the case upon the patient who seeks to recover in a malpractice action for her injury.

In considering the obligation of a physician to disclose and explain to the patient in language as simple as necessary the nature of the ailment, the nature of the proposed treatment, the probability of success or of alternatives, and perhaps the risks of unfortunate results and unforeseen conditions within the body, we do not think the administration of such an obligation, by imposing liability for malpractice if the treatment were administered without such explanation where explanation could reasonably be made, present's any insurmountable obstacles.

*411 The appellant’s requested instruction on the duty of a physician to make a disclosure to his patient was too broad. But this did not relieve the trial court of its obligation to instruct on such issue under the circumstances here presented, since the issue was raised by the pleadings. On retrial the instruction should be modified to inform the jury that a physician has such discretion, as heretofore indicated, consistent with the full disclosure of facts necessary to assure an informed consent by the patient.

On retrial of this case the first issue for the jury to determine should be whether the administration of cobalt irradiation treatment was given with the informed consent of the patient, and if it was not, the physician who failed in his legal obligation is guilty of malpractice no matter how skillfully the treatment may have been administered, and the jury should determine the damages arising from the cobalt irradiation treatment. If the jury should find an informed consent was given by the patient for such treatment, the jury should next determine whether proper skill was used in administering the treatment.

The primary basis of liability in a malpractice action is the deviation from the standard of conduct of a reasonable and prudent medical doctor of the same school of practice as the defendant under similar circumstances. Under such standard the patient is properly protected by the medical profession’s own recognition of its obligations to maintain its standards.

The appellant requested and the trial court refused to give the following instruction:

“You are instructed that under the terms of the contract between defendant Kline and defendant Hospital it was the duty of defendant Kline to supervise the work of all the personnel in the radiology department. If you find that plaintiff’s injury was the result of the negligence of personnel in the department your verdict shall be in favor of plaintiff and against both defendants.”

Nowhere in the written instructions was there anything to indicate that either defendant could be chargeable with the negligence of anyone other than the negligence of Dr. Kline personally, unless it is to be construed from the generalization of the pleadings contained in the court’s instruction No. 1. This generalization at best would be confusing to a jury on this point.

“A physician is responsible for an injury done to a patient through the want of proper skill and care in his assistant, and through the want of proper skill and care in his apprentice, agent, or employee. The fact that a physician’s assistant is a member of the same or a similar profession does not make the *412 rule of respondeat superior inapplicable, and a physician is liable not only for negligence of laymen employed by him, but also for the negligence of nurses or other physicians in his employ.

“Corporations, or persons other than physicians, who treat patients for hire with the expectation of profit are liable for negligence or malpractice on the part of the physicians or nurses employed by them.” (70 C. J. S., Physicians and Surgeons, § 54e, pp. 978, 979, and see cases cited therein.)

Although the court did not think it necessary to go into the doctrine of respondeat superior, see the facts in Rule v. Cheeseman, Executrix, 181 Kan. 957, 317 P. 2d 472.

In Gray v. McLaughlin, 207 Ark. 191, 179 S. W. 2d 686, an X-ray specialist or roentgenologist was held liable for injuries caused by the X-ray technician employed by him.

In an action for damages founded on malpractice it is the duty of the trial court to instruct the jury with respect to the law governing the case, explaining the precise questions at issue. This includes, under the evidence presented by the record in the instant case, the responsibility of the physician for the acts or omissions of others under his supervision. (See, 70 C. J. S., Physicians and Surgeons, § 64, p. 1016, and cases cited.)

A party is entitled to have the trial court give an instruction to the jury which is essential to his theory of the case when there is sufficient evidence to support such theory. (Kreh v. Trinkle, 185 Kan. 329, 343 P. 2d 213.)

In our opinion the refusal of the trial court to give the requested instruction was prejudicial and constituted reversible error. It was Dr. Somers, not Dr. Kline, who prescribed use of rotational therapy. Dr. Somers was an assistant to Dr. Kline. It was the hospital’s employee, Darter, referred to by Dr. Kline as his physicist, who made the computations which resulted in administration of a dosage in excess of tolerance limits, if the jury were to give credence to the appellant’s theory of the evidence, and Dr. Kline was chargeable with knowledge of the quantity and effect of the irradiation he caused to be administered to the appellant. (Agnew v. Larson, 82 Cal. App. 2d 176, 185 P. 2d 851.)

While counsel for the appellees made no objection to the testimony of Dr. Roys, they set forth in detail his testimony in a counter abstract to show he was not a physician but was testifying by virtue of an academic degree. Inferentially this may suggest Dr. Roys, not being a physician of the same school of practice as Dr. Kline. *413 was incompetent to establish negligence concerning medical practice and treatment. (Goheen v. Graber, 181 Kan. 107, 309 P. 2d 636.)

It is the customary practice, however, for a radiologist to have a physicist make his calculations where cobalt irradiation therapy treatments are given by a rotational beam to patients. This was confirmed not only by Dr. Kline but also by Dr. Hare. In fact, Dr. Kline testified that he did not know how to make the calculations necessary to make the irradiation administered meet the requirements for the radiation prescribed. He said he could not even understand the calculations when they had been made by others. It must be observed this is not unusual because the radiologist is not trained in nuclear physics, a specialty in itself. Dr. Roys was a technician of the same type as Darter, and, in fact, was the professor at Wichita University under whom Darter studied. Thus, there could be no legitimate objection to the competency of Dr. Roys to testify relative to the calculations made.

The appellees contend that no issue was raised in the pleadings or in the evidence at the trial, so far as the jury was concerned, which would exempt the hospital from liability for the acts of Dr. Kline under the doctrine of respondeat superior and that by reason thereof no instruction was required. The simple answer is that the appellees are privileged to make this admission, but the jury is entitled by an appropriate instruction to know about it. The appellees argue the appellant does not claim that Darter made any error in computation. While this is true, Darter did not, under the appellant’s theory, make enough calculations to know that an excessive equilibrium dosage was administered five millimeters beneath the skin. Under these circumstances, the appellees’ argument has no merit.

The appellant contends the trial court erred in failing to instruct that the jury might consider the fact of injury as evidence of negligence, citing George v. Shannon, 92 Kan. 801, 142 Pac. 967. On the facts presently before the court this point is not well taken. The appellant alleges injury as a result of burns from cobalt irradiation therapy. This is not a res ipsa loquitur case and no presumption of negligence of a physician is to be indulged from the fact of injury or adverse result of his treatment of the patient. (Cummins v. Donley, 173 Kan. 463, 249 P. 2d 695, and cases cited therein.)

*414 In Costa v. Regents of Univ. of California, supra, it was contended, among other things, that necrosis did not ordinarily follow treatment from cancer X ray and that this circumstance amounted to proof of negligence. In rejecting the contention the California court said:

“. . . The result of the same treatment is not always the same in all cases and on all patients. When the result of a treatment is less favorable or more prejudicial than in the great majority of cases such need not indicate that the treatment was negligently performed, but may as well be the result of individual differences in reaction or the less favorable circumstances of the case . . .” (p. 461.)

The expert testimony in the instant case confirms the correctness of the above statement. (But see, King v. Ditto, 142 Ore. 207, 19 P. 2d 1100.)

Upon the record presented it is apparent the appellees were united in interest; therefore, pursuant to G. S. 1949, 60-2907, the appellees were obligated in the exercise of their peremptory challenges in empaneling the jury to challenge jointly.

In conclusion we hold the trial court committed reversible error in the matter of instructing the jury. It has been held when the instructions to the jury define the issues and state the pertinent law with accuracy, the failure of the court to emphasize some particular point of law deemed important by a party litigant does not constitute error, especially when such party does not object to the instructions as given nor ask for a further instruction to supplement them. (Kiser v. Skelly Oil Co., 136 Kan. 812, 18 P. 2d 181.) In the instant case the instructions given to the jury did not define the issues and state the pertinent law with accuracy, and further instructions were requested. By reason of the errors heretofore noted the appellant should be granted a new trial.

The judgment of the lower court is reversed with directions to grant a new trial.

*187The opinion of the court was delivered by

Schroeder, J.:

Within the time allotted after the decision of the court herein was announced the appellees filed motions for rehearing. Thereafter, pursuant to request, leave was granted the Kansas Medical Society on May 12, 1960, to file its brief amicus curiae in support of the appellees’ motions for rehearing. Finding nothing, upon consideration of the motions for rehearing and the brief of amicus curiae in support thereof, which warrants a reconsideration of the case, the motions for rehearing are denied.

Recognizing, however, that this is a case of first impression in Kansas and one establishing judicial precedence of the highest importance to the medical profession, an attempt will be made to clarify Syllabus ¶ 4 and the corresponding portion of the opinion concerning which counsel are apprehensive.

Perhaps in preoccupation over the legal obligation of a physician to his patient, the court has not adequately emphasized procedural aspects of the case, or reiterated fundamental doctrine in the law of negligence sufficiently to completely avoid efforts to misconstrue the opinion.

It is charged that the court has confused a malpractice suit, where negligence is an essential element, with an assault and battery case, where negligence is not an essential element, thereby giving rise to a hybrid action which is neither one of negligence nor one of assault and battery, but may be a combination of the two.

It is argued the only way the court’s opinion can be justified is to say that the duty of a physician to disclose to his patient the risks and hazards of a proposed form of treatment is an absolute one, and the matter is not to be judged by such disclosures as a reasonable medical practitioner would make under the same or similar circumstances.

In support of the argument, that the court has imposed an absolute duty upon the physician, the following paragraph is isolated from context:

“On retrial of this case the first issue for the jury to determine should be whether the administration of cobalt irradiation treatment was given with the informed consent of the patient, and if it was not, the physician who failed in his legal obligation is guilty of malpractice no matter how skillfully the treatment may have been administered, and the jury should determine the damages *188arising from the cobalt irradiation treatment. If the jury should find an informed consent was given by the patient for such treatment, the jury should next determine whether proper skill was used in administering the treatment.” (Natanson v. Kline, 186 Kan. 393, 411, 350 P. 2d 1093.)

A casual reading of this paragraph in context would indicate that reference is there being made to the order in which the jury is to consider the issues presented on retrial of the case, and not to an enumeration of the various elements which must be established by the evidence to prove each of the issues stated.

The gravamen of the plaintiff’s complaint was malpractice or the failure of the defendants to properly perform the duties which devolved upon them — a failure which resulted in the alleged injuries to the plaintiff. Thus it was incumbent upon the plaintiff to prove and establish (1) that the defendants failed to perform their duty; and (2) that the plaintiff’s injuries were the direct and proximate result of such failure.

The petition alleged that the injuries were “a direct and proximate result of the defendants’ negligence and carelessness” and then set forth eight specific grounds of negligence, including:

“(g) He [Dr. Kline] failed to warn plaintiff that the course of treatment which he undertook to administer involved great risk of bodily injury or death.”

The answers of both defendants denied generally the allegations of asserted negligence, and in addition thereto, affirmatively pleaded that the plaintiff “assumed the risk and hazard of the treatment.” Thus, at the trial the defendants were fully aware that the informed consent of the patient to the hazards of the treatment was an issue of fact in the case. This is true because as a defense assumption of risk is applicable only where the plaintiff is equally competent with the defendant to judge concerning the risks and hazards. (See, Taylor v. Hostetler, 186 Kan. 788, 352 P. 2d 1042, and cases cited therein.) These affirmative allegations of the defendants presupposed an informed consent by the patient with full knowledge of the risks and hazards of the treatment.

The court held after reviewing the record presented on this appeal that a physician violates his duty to his patient and subjects himself to liability for malpractice, where no immediate emergency exists and upon facts and circumstances particularly set forth in the opinion, if he makes no disclosure of significant facts within his knowledge which are- necessary to form the basis of an intelligent consent by the patient to the proposed form of treatment (Syllabus ¶ 4).

*189In other words, on the facts and circumstances presented by the record the appellant was entitled to some explanation concerning the risks and hazards inherent in the administration of cobalt irradiation treatment which Dr. Kline proposed to administer to her. For this treatment she was Dr. Kline’s patient and not the patient of Dr. Crumpacker by whom she was referred to Dr. Kline.

The appellant was entitled to a reasonable disclosure by Dr. Kline so that she could intelligently decide whether to take the cobalt irradiation treatment and assume the risks inherent therein, or in the alternative to decline this form of precautionary treatment and take a chance that the cancerous condition in her left breast had not spread beyond the lesion itself which had been removed by surgery. There was no emergency calling for immediate attention. The appellant had recovered from the surgery. In addition to the evidence related in the opinion her husband testified:

“Q. Now, directing your attention to approximately the 5th or 6th day of June, 1955, I would like to have you describe for us the general apparent condition of the health of Mrs. Natanson?

“A. Mrs. Natanson at that particular time was very, very well. She had gone through the two operations and had made a very, very fine recovery. She was able to use her arm because of the therapy; she had almost the complete use of the left arm again. The breast had healed fully. There were actually no scars — just the one large scar but there was a thickness there. We were living a very normal life after the big scare we had.

“Q. Now, directing your attention to the first week of June, 1955, I will ask you whether or not Mrs. Natanson ever recovered to the point where she was able to do her own housework?

“A. Yes, she had/"

But contrary to the legal obligation imposed upon a physician to make a reasonable disclosure to his patient of the inherent risks and hazards of a proposed form of treatment, Dr. Kline gave the appellant no explanation whatever. He made no disclosures. He was silent. On this state of the record Dr. Kline failed in his legal duty to make a reasonable disclosure to the appellant who was his patient as a matter of law.

Conceivably, in a given case as indicated in the opinion, no disclosures to a patient may be justified where such practice, under given facts and circumstances, is established by expert testimony to be in accordance with that of a reasonable medical practitioner under the same or similar circumstances. But on the state of the record here presented the appellant was not required to produce expert medical testimony to show that the failure of Dr. Kline to *190give any explanation or make any disclosures was contrary to accepted medical practice. To hold otherwise would be a failure of the court to perform its solemn duty.

Whether or not a physician has advised his patient of the inherent risks and hazards in a proposed form of treatment is a question of fact concerning which lay witnesses are competent to testify, and the' establishment of such fact is not dependent upon expert medical testimony. It is only when the facts concerning the actual disclosures made to the patient are ascertained, or ascertainable by the trier of the facts, that the expert testimony of medical witnesses is required to establish whether such disclosures are in accordance with those which a reasonable medical practitioner would make under the same or similar circumstances.

The question then remains whether such failure on the part of Dr. Kline to make a reasonable disclosure to the appellant was a proximate cause of her injury. As indicated in the opinion the mere fact that Dr. Kline was silent does not compel a verdict for the appellant. It was said:

“. . . Under the rule heretofore stated, where the patient fully appreciates the danger involved, the failure of a physician in his duty to make a reasonable disclosure to the patient would have no causal relation to the injury. In such event the consent of the patient to the proposed treatment is an informed consent. The burden of proof rests throughout the trial of the case upon the patient who seeks to recover in a malpractice action for her injury.” (Natanson v. Kline, supra, p. 410.)

Negligence is an essential element of malpractice, and the foregoing statement recognizes that a causal relation must be established by the patient, between the negligent act of the physician and the injury of the patient, to sustain the burden of proof where damages are sought in a malpractice action for injury. Prior to a discussion of the manner in which the court instructed the jury it was said in the opinion:

“. . . At best it may be said, upon all the facts and circumstances presented by the record, there was evidence from which a jury could find that the proximate cause of the appellant’s injury was the negligence of the defendants. On the other hand a jury, properly instructed, would be justified in finding for the appellees.” (Natanson v. Kline, supra, p. 898.)

After making the foregoing statement in the opinion, discussion was directed to the instructions of the court without further specific attention to the issue of proximate cause. If, of course, the appellant would have taken the cobalt irradiation treatments even though Dr. Kline had warned her that the treatments he undertook to administer *191involved great risk of bodily injury or death, it could not be said that the failure of Dr. Kline to so inform the appellant was the proximate cause of her injury. While the appellant did not directly testify that she would have refused to take the proposed cobalt irradiation treatments had she been properly informed, we think the evidence presented by the record taken as a whole is sufficient and would authorize a jury to infer that had she been properly informed, the appellant would not have taken the cobalt irradiation treatments.

Two days after the decision of this court was announced, the Supreme Court of Missouri handed down its opinion in Mitchell v. Robinson, 334 S. W. 2d 11, on April 11, 1960, wherein the Missouri court reached the same conclusion as this court on the duty of a physician to inform his patient of the hazards of treatment. There the patient had a rather severe emotional illness but was not mentally incompetent. The treatment prescribed was “combined electroshock and insulin subcoma therapy.” A sharp conflict developed in the testimony as to whether the patient was informed of the risks of the treatment. Serious hazards incident to shock treatment were admitted, to-wit: fractured bones, serious paralysis of limbs, irreversible coma and even death, and further that there were no completely reliable or successful precautions. The patient as a result of treatment went into convulsions which caused the fracture of several vertebrae and sued the physicians in a malpractice action on the ground that he was not informed of the risks inherent in the treatment. The “essentially meritorious problem” before the court was whether upon the record there was any evidence to support the jury’s finding of negligence. In the opinion the court said:

“In the particular circumstances of this record, considering the nature of Mitchell’s illness and this rather new and radical procedure with its rather high incidence of serious and permanent injuries not connected with the illness, the doctors owed their patient in possession of his faculties the duty to inform him generally of the possible serious collateral hazards; and in the detailed circumstances there was a submissible fact issue of whether the doctors were negligent in failing to inform him of the dangers of shock therapy.” (p. 19.)

As always, an effort is made by the court to present an opinion in logical sequence, so that consideration of subsequent issues is dependent upon the disposition of issues previously determined, and if opinions are analyzed in this manner misinterpretations will be minimized.

Parker, C. J., and Price, J.,

are of the opinion the judgment of the trial court should be affirmed, and therefore dissent.

SPOTTSWOOD W. ROBINSON, III, Circuit Judge:

This appeal is from a judgment entered in the District Court on verdicts directed for the two appellees at the conclusion of plaintiff-appellant Canterbury’s case in chief. His action sought damages for personal injuries allegedly sustained as a result of an operation negligently performed by appellee Spence, a negligent failure by Dr. Spence to disclose a risk of serious disability inherent in the operation, and negligent post-operative care by appellee Washington Hospital Center. On close examination of the record, we find evidence which required submission of these issues to the jury. We accordingly reverse the judgment as to each appellee and remand the case to the District Court for a new trial.

I

The record we review tells a depressing tale. A youth troubled only by back pain submitted to an operation without being informed of a risk of paralysis incidental thereto. A day after the operation he fell from his hospital bed after having been left without assistance while voiding. A few hours after the fall, the lower half of his body was paralyzed, and he had to be operated on again. Despite extensive medical care, he has never been what he was before. Instead of the back pain, even years later, he hobbled about on crutches, a vietim of paralysis of the bowels and urinary incontinence. In a very real sense this lawsuit is an understandable search for reasons.

At the time of the events which gave rise to this litigation, appellant was nineteen years of age, a clerk-typist employed by the Federal Bureau of Investigation. In December, 1958, he began to experience severe pain between his shoulder blades. 1 He consulted two general practitioners, but the medications they prescribed failed to eliminate the pain. Thereafter, appellant secured an appointment with Dr. Spence, who is a neurosurgeon.

Dr. Spence examined appellant in his office at some length but found nothing amiss. • On Dr. Spence’s advice appellant was x-rayed, but the films did not identify any abormality. Dr. Spence then recommended that appellant undergo a myelogram — a procedure in which dye is injected into the spinal column and traced to find evidence of disease or other disorder — at the Washington Hospital Center.

Appellant entered the hospital on February 4, 1959. 2 Thg myelogram revealed a “filling defect” in the region of the fourth thoracic vertebra. Since a myelogram often does no more than pinpoint *777 the location of an aberration, surgery may be necessary to discover the cause. Dr. Spence told appellant that he would have to undergo a laminectomy — -the excision of the posterior arch of the vertebra — to correct what he suspected was a ruptured disc. Appellant did not raise"! any objection to the proposed operation nor did he probe into its exact nature.

Appellant explained to Dr. Spence that his mother was a widow of slender financial means living in Cyclone, West Virginia, and that she could be reached through a neighbor’s telephone. Appellant called-his mother the day after the myelogram was performed and, failing to contact her, left Dr. Spence’s telephone number with the neighbor. When Mrs. Canterbury returned the call, Dr. Spence told her that the surgery was occasioned by a suspected ruptured disc. Mrs. Canterbury then asked if the recommended-operation was serious and Dr. Spence replied “not anymore than any other operation.” He added that he knew Mrs. Canterbury was not well off and that her presence in Washington would not be necessary. The testimony is contradictory as to whether during the course of the conversation Mrs. Canterbury expressed her consent to the operation. Ap pellant himself apparently did not converse again with Dr. Spence prior to the operation.

Dr. Spence performed the laminectomy on February 11 3 at the Washington Hospital Center. Mrs. Canterbury traveled to Washington, arriving on that date but after the operation was over, and signed a consent-form at .the hospital. The laminectomy revealed several anomalies : a spinal cord that was swollen and unable to pulsate, an accumulation of large tortuous and dilated veins, and a complete absence of epidural fat which normally surrounds the spine. A thin hypodermic needle was inserted into the spinal cord to aspirate any cysts which might have .been present, but no fluid emerged. In suturing the wound, Dr. Spence attempted to relieve the pressure on the spinal cord by enlarging the dura —the outer protective wall of the spinal eord^-at the area of swelling.

For approximately the first day after the operation appellant recuperated normally, but then suffered a fall and an almost immediate setback. Since there is some conflict as to precisely when or why appellant fell, 4 we reconstruct the events from the evidence most favorable to him. 5 Dr. Spence left orders that appellant was to remain in bed during the process of voiding. These orders were changed to direct that voiding be done out of bed, and the jury could find that the change was made by hospital personnel. Just prior to the fall, appellant summoned a nurse and was given a receptacle for use in voiding, but was then left unattended. Appellant testified that during the course of the endeavor he slipped off the side of the bed, and that there was no one to assist him, or side rail to prevent the fall.

Several hours later, appellant began to complain that he could not move his legs and that he was having trouble breathing; paralysis seems to have been virtually total from the waist down. Dr. Spence was notified on the night of February 12, and he rushed to the hospital. Mrs. Canterbury signed another consent form and appellant was again taken into the operating room. The surgical wound was reopened and Dr. Spense created a gusset to allow the spinal cord greater room in which to pulsate.

Appellant’s control over his muscles improved somewhat after the second operation but he was unable to void properly. As a result of this condition, he came under the care of a urologist while *778 still in the hospital. In April, following a cystoscopic examination, appellant was operated on for removal of bladder stones, and in May was released from the hospital. He reentered the hospital the following August for a 10-day period, apparently because of his urologic problems. For several years after his discharge he was under the care of several specialists, and at all times was under the care of a urologist. At the time of the trial in April, 1968, appellant required crutches to walk, still suffered from urinal incontinence and paralysis of the bowels, and wore a penile clamp.

In November, 1959 on Dr. Spence’s recommendation, appellant was transferred by the F.B.I. to Miami where he could get more swimming and exercise. Appellant worked three years for the F.B.I. in Miami, Los Angeles and Houston, resigning finally in June, 1962. From then until the time of the trial, he held a number of jobs, but had constant trouble finding work because he needed to remain seated and close to a bathroom. The damages appellant claims include extensive pain and suffering, medical expenses, and loss of earnings.

II

Appellant filed suit in the District Court on March 7, 1963, four years after the laminectomy and approximately two years after he attained his majority. The complaint stated several causes of action against each defendant. Against Dr. Spence it alleged, among other things, negligence in the performance of the laminectomy and failure to inform him beforehand of the ..risk involved. Against the hospital the complaint charged negligent post-operative care in permitting appellant to remain unattended after the laminectomy, in failing to provide a nurse or orderly to assist him at the time of his fall, and in failing to maintain a side rail on his bed. The answers denied the allegations of negligence and defended on the ground that the suit was barred by the statute of lim-** itations.

Pretrial discovery — including depositions by appellant, his mother and Dr. Spence — continuances and other delays consumed five years. At trial, disposition of the threshold question whether the statute of limitations had run was held in abeyance until the relevant facts developed. Appellant introduced no evidence to show medical and hospital practices, if any, customarily pursued in regard to the critical aspects of the case, and only Dr. Spence, called as an adverse witness, testified on the issue of causality. Dr. Spence described the surgical procedures he utilized in the two operations and expressed his opinion that appellant’s disabilities stemmed from his pre-operative condition as symptomized by the swollen, non-pulsating spinal cord. He stated, however, that neither he nor any of the other physicians with whom he consulted was certain as to what that condition was, and he admitted that trauma can be a cause of paralysis. Dr. Spence further testified that even without trauma paralysis can be anticipated “somewhere in the nature of one percent” of the laminectomies performed, a risk he termed “a very slight possibility.” He .feltthat .communication of that..risk-to the patient is not good medical practice because it might deter 'patients. from undergoing needed surgery and might produce' adverse psychological reactions which eoúld preclude the success of the operation.

At the close of appellant’s case in chief, each defendant moved for a directed verdict and the trial judge granted both motions. The basis of the ruling, he explained, was that appellant had failed to produce any medical evidence indicating negligence on Dr. Spence’s part in diagnosing appellant’s malady or in performing the laminectomy; that there was no proof that Dr. Spence’s treatment was responsible for appellant’s disabilities; and that notwithstanding some evidence to show negligent post-operative care, an absence of medical testimony to show causality precluded submission of the case against the hospital to the jury. *779 The judge did not allude specifically to the alleged breach of duty by Dr. Spence to divulge the possible consequences of the laminectomy.

We reverse. The testimony of appellant and his mother that Dr. Spence did not reveal the risk of paralysis from the laminectomy made out a prima facie case of violation of the physician’s duty to disclose which Dr. Spence’s explanation-did not negate as a matter of law. There was also testimony from which the jury could have found that the laminectomy was negligently performed by Dr. Spence, and that appellant’s fall was the consequence of negligence on the part of the hospital. The record, moreover, contains evidence of sufficient quantity and quality to tender jury issues as to whether and to what extent any such negligence was causally related to appellant’s post-laminectomy condition. These considerations entitled appellant to a new trial.

Elucidation of our reasoning necessitates elaboration on a number of points. In Parts III and IV we explore the origins and rationale of the physician’s duty to reasonably inform an ailing patient as to the treatment alternatives available and the risks incidental to them. In Part V we investigate the scope of the disclosure requirement and in Part VI the physician’s privileges not to disclose. In Part VII we examine the role of causality, and in Part VIII the need for expert testimony in non-disclosure litigation. In Part IX we deal with appellees’ statute of limitations defense and in Part X we apply the principles discussed to the case at bar.

Ill

Suits charging failure by a physician 6 adequately to disclose the risks and alternatives of proposed treatment are not innovations In American law. They date back a good half-century, 7 and in the last decade they have multiplied rapidly. 8 There is, nonetheless, disagreement among the courts and the commentators 9 on many major questions, and there is no precedent of our own directly in point. 10 For the tools enabling resolu *780 tion of the issues on this appeal, we are forced to begin at first principles. 11

The root premise is the concept, fundamental in American jurisprudence, that “[e]very human being of adult years and sound mind has a right to determine what shall be done with his own body. . . . ” 12 True consent to what happens to one’s self is the informed exercise of a choice, and that entails an opportunity to evaluate knowledgeably the options available and the risks attendant upon each. 13 The average patient has little or no understanding of the medical arts, and ordinarily has only his physician to whom he can look for enlightenment with which to reach an intelligent decision. 14 From these almost axiomatic considerations springs the need, and in turn the requirement, of a reasonable divulgenee by physician to patient to make such a decision possible. 15

*781 A physician is under a duty to treat his patient skillfully 16 but proficiency in diagnosis and therapy is not the full measure of his responsibility. The cases demonstrate that the physician is under an obligation to communicate specific information to the patient when the exigencies of reasonable care call for it. 17 Due care may require a physician perceiving symptoms of bodily abnormality to alert the patient to the condition. 18 It may call upon the physician confronting an ailment which does not respond to his ministrations to inform the patient thereof. 19 It may command the physician to instruct the patient as to any limitations to be presently observed for his own welfare, 20 and as to any precautionary therapy he should seek in the future. 21 It may oblige the physician to advise the patient of the need for or desirability of any alternative treatment promising greater benefit than that being pursued. 22 Just as plainly, due care normally demands that the physician warn the patient of any risks to his well-being which contemplated therapy may involve. 23

The context in which the duty of risk-disclosure arises is invariably the occasion for decision as to whether a particular treatment procedure is to be undertaken. To the physician, whose training enables a self-satisfying evaluation, the answer may seem clear, but it is the prerogative of the patient, not the physician, to determine for himself the direction in which his interests seem to lie. 24 To enable the patient to chart his course understandably, some familiarity with the therapeutic alternatives and their hazards becomes essential. 25

*782 A reasonable revelation in these respects is not only a necessity but, as we see it, is as much a matter of the physician’s duty. Ijt is a duty to warn of the dangers lurking in the proposed treatment, and that is surely a facet of due care. 26 It is, too, a duty to impart information which the patient has every right to expect. 27 The patient’s reliance upon the physician is a trust of the kind which traditionally has exacted obligations beyond those associated with arms-length transactions. 28 His dependence upon the physician for information affecting his well-being,' in terms of contemplated treatment, is well-nigh abject. As earlier noted, long before the instant litigation arose, courts had recognized that the physician had the responsibility of satisfying the vital informational needs of the patient. 29 | More recently, we ourselves have found “in the fiducial qualities of [the physician-patient] relationship the physician’s duty to reveal to the patient that which in his best interests it is important that he should know.” 30 We now find, as a part of the physician’s overall obligation to the patient, a similar duty of reasonable disclosure of the choices with respect to proposed therapy and the dangers inherently and potentially involved. 31

This disclosure requirement, on analysis, reflects much more of a change in doctrinal emphasis than a substantive addition to malpractice law. It is well established that the physician must seek and secure his patient’s consent before commencing an operation or other course of treatment. 32 It is also *783 clear that the consent, to be efficacious, must be free from imposition upon the patient. 33 It is the settled rule that therapy not authorized by the patient may amount to a tort — a common law battery —by the physician. 34 And it is evident that it is normally impossible to obtain a consent worthy of the name unless the physician first elucidates the options and the perils for the patient’s edification. 35 Thus the physician has long borne a duty, on pain of liability for unauthorized treatment, to make adequate disclosure to the patient. 36 The evolution of the obligation to communicate for the patient’s benefit as well as the physician’s protection has hardly involved an extraordinary restructuring of the law.

IV

Duty to disclose has gained recognition in a large number of American jurisdietions, 37 but more largely on a different rationale. The majority of courts dealing with the problem have made the duty depend on whether it was the custom of physicians practicing in the community to make the particular disclosure to the patient. 38 If so, the physician may be held liable for an unreasonable and injurious failure to divulge, but there can be no recovery unless the omission forsakes a practice prevalent in the profession. 39 We agree that the physician’s noncompliance with a professional custom to reveal, like any other departure from prevailing medical practice, 40 may give rise to liability to the patient. We do not agree that the patient’s cause of action is dependent upon the existence and nonperformance of a relevant professional tradition.

There are, in our view, formidable obstacles to acceptance of the notion that the physician’s obligation to disclose is either germinated or limited by medical practice. To begin with, the reality of any discernible custom reflecting a professional concensus on communication of option and risk information to patients is open to serious doubt. 41 We sense the danger that what in fact is no *784 custom at all may be taken as an affirmative custom to maintain silence, and that physician-witnesses to the so-called custom may state merely their personal opinions as to what they or others would do under given conditions. 42 We cannot gloss over the inconsistency between reliance on a general practice respecting divulgence and, on the other hand, realization that the myriad of variables among patients 43 makes each case so different that its omission can rationally be justified only by the effect of its individual circumstances. 44 Nor can we ignore the fact that to bind the disclosure obligation to medical usage is to arrogate the decision on revelation to the physician alone. 45 Respect for the patient’s right of self-determination on particular therapy 46 demands a standard set by law for physicians rather than one which physicians may or may not impose .upon themselves. 47

More fundamentally, the majority rule overlooks the graduation of reasonable-care demands in Anglo-American jurisprudence and the position of professional custom in the hierarchy. The caliber of the performance exacted by the reasonable-care standard varies between the professional and non-professional worlds, and so also the role of professional custom. “With but few exceptions,” we recently declared, “society demands that everyone under a duty to use care observe minimally a general standard.” 48 “Familiarly expressed judicially,” we added, “the yardstick is that degree of care which a reasonably prudent person would have exercised under the same or similar circumstances." 49 “Beyond this,” however, we emphasized, “the law requires those engaging in activities requiring unique knowledge and ability to give a performance commensurate with the undertaking.” 50 Thus physicians treating the sick must perform at higher levels than non-physicians in order to meet the reasonable care standard in its special application to physicians 51 — “that degree of care and skill ordinarily exercised by the profession in [the physician’s] own or similar localities.” 52 And practices adopted by the profession have indispensable value as evidence tending to establish just what that degree of care and skill is. 53

We have admonished, however, that “[t]he special medical standards 54 are but. adaptions of the general standard to a group who are required to act as *785 reasonable men possessing their medical talents presumably would.” 55 There is, by the same token, no basis for operation of the special medical standard where the physician’s activity does not bring his .medical knowledge and skills peculiarly .into play. 56 And where the challenge to the physician’s conduct is not to be gauged by the special standard, it follows that medical custom cannot furnish the test of its propriety, whatever its relevance under the proper test may be. 57 The decision to unveil the patient’s condition and the chances as to remediation, as we shall see.Js ofttimes a non-medical judgment 58 and, if so, is a decision out.side the ambit of the special standard. Where that is the situation, professional custom hardly furnishes the legal criterion for measuring the physician’s responsibility to reasonably inform his patient of the options and the hazards as to treatment.

The majority rule, moreover, is at war with our prior holdings that a showing of medical practice, however probative, does not fix the standard governing recovery for medical malpractice. 59 .Prevailing medical practice, we have maintained, has_evidentiary value in determinations as to what the specific criteria measuring challenged professional conduct are and whether they have been met, 60 but does not itself define the standard. 61 That has been our position in treatment cases, where the physician’s performance is ordinarily to be adjudicated by the special medical standard of due care. 62 We see no logic in a different rule for nondisclosure cases, where the governing standard is much more largely divorced from professional considerations. 63 And surely in nondisclosure cases the factfinder is not invariably functioning in an area of such technical complexity that it must be bound to medical custom as an inexorable application of the community standard of reasonable care. 64

Thus we distinguished, for purposes of duty to disclose, the speeial- and general-standard aspects of the physician-patient relationship. When medical judgment enters the picture and for 'that reason the special standard controls, prevailing medical practice must be given its just due. In all other instances, however, the general standard exacting ordinary care applies, and that standard is set by law. In sum, the physician’s duty to disclose is governed by the same legal principles applicable to others in comparable situations, with modifications only to the extent that medical judgment enters the picture. 65 We hold that the standard measuring, performance of that duty by physicians, as by others, is conduct which is reasonable under the circumstances. 66

*786 V

Once the circumstances give rise to a duty on the physician’s part to inform his patient, the next inquiry is the_scope of the disclosure the physician is legally obliged to make. The courts have frequently confronted this problem but no uniform standard defining the adequacy of the divulgenee emerges from the decisions. Some have said “full” disclosure, 67 a norm we are unwilling to adopt literally. It seems obviously prohibitive and unrealistic to expect physicians to discuss with their patients every risk of proposed treatment — no matter how small or remote 68 — and generally unnecessary from the patient’s viewpoint as well. Indeed, the cases speaking in terms of “full” disclosure appear to envision something less than total disclosure, 69 leaving unanswered the question of just how much.

The larger number of courts, as might be expected, have applied tests framed with reference to prevailing fashion within the medical profession. 70 Some have measured the disclosure by “good medical practice,” 71 others by what a reasonable practitioner would have bared under the circumstances, 72 and still others by what medical custom in the community would demand. 73 JVe have explored this rather considerable body of law but are unprepared to follow it. The duty to disclose, we have reasoned, arises from phenomena apart from medical custom and practice. 74 The latter, we think, should no more establish the scope of the duty than its existence. Any definition of scope in terms purely of a professional standard is at odds with the patient’s prerogative to decide on projected therapy himself. 75 That prerogative, we have said, is at the very foundation of the duty to disclose, 76 and both the patient’s right to know and the physician’s correlative obligation to tell him are diluted to the extent that its compass is dictated by the medical profession. 77

In our view, the patient’s right of self-decision shapes the boundaries of the duty to reveal. That right can be effectively exercised only if the patient possesses enough information to enable an intelligent choice.’ The scope of the physician’s communications to the patient, then, must bef measured by the patient’s need, 78 and that need is the information material to the decision. Thus tlie test for determining whether a par *787 ticular peril must be divulged is its materiality to the patient’s decision: all risks, potentially affecting the decision must be unmasked. 79 And to safeguard the patient’s interest in achieving his own determination on treatment, the law must itself set the standard for adequate disclosure. 80

Optimally for the patient, exposure of a risk would be mandatory whenever the patient would deem it significant to his decision, either singly or in combination with other risks. Such a requirement, however, would summon the physician to second-guess the patient, whose ideas on materiality could hardly be known to the physician. That would make an undue demand upon medical practitioners, whose conduct, like that of others, is to be- measured in terms of reasonableness. Consonantly with orthodox negligence doctrine, the physician’s liability for nondisclosure is to be determined on the basis of foresight, not hindsight; no less than any other aspect of negligence, the issue on nondisclosure must be approached from the viewpoint of the reasonableness of the physician’s divulgence jn terms of what he knows or should know to be the patient’s informational needs. If, but only if, the fact-finder can say that the physician’s communication was unreasonably inadequate is an imposition of liability legally or morally justified. 81

Of necessity, the content of the disclosure rests in the first instance with the physician. Ordinarily it is only he who is in position to identify particular dangers; always he must make a judgment, in terms of materiality, as to whether and to what extent revelation to the patient is called for. He cannot know with complete exactitude what the patient would consider important to his decision, but on the basis of his medical training and experience he can sense how the average, reasonable patient expectably would react. 82 Indeed, with knowledge of, or ability to learn, his patient’s background and current condition, he is in a position superior to that of most others — attorneys, for example — who are called upon to make judgments on pain of liability in damages for unreasonable miscalculation. 83

From these considerations we derive the breadth of the disclosure of risks legally to be required. The scope of the standard is not subjective as to either the physician or the patient; it remains objective with due regard for the patient’s informational needs and with suitable leeway for the physician’s situation. In broad outline, we agree that,“[a] risk is thus material when a reasonable person, in what the physician knows or should know to be the patient’s position, would be likely to attach significance to the risk or.cluster of risks in deciding whether or not to forego the proposed therapy.” 84

The topics importantly demanding a communication of information are the inherent and potential hazards of the proposed treatment, the alternatives to *788 that treatment, if any, and the results likely if the patient remains untreated. The factors contributing significance to the dangerousness of a medical technique are, of course, the incidence of injury and the degree of the harm threatened. 85 A very small chance of death or serious disablement may well be significant; a potential disability which dramatically outweighs the potential benefit of the therapy or the detriments of the existing malady may summons discussion with the patient 86

There is no bright line separating the significant from the insignificant ; the answer in any case must abide a rule of reason. Some dangers — infection, for example — are inherent in any operation; there is no obligation to communicate those of which persons of average sophistication are aware. 87 Even more clearly, the physician bears no responsibility for discussion of hazards the patient has already discovered, 88 or those having no apparent materiality to patients’ decision on therapy. 89 The disclosure doctrine, like others marking lines between permissible and impermissible behavior in medical practice, is in essence a requirement of conduct prudent under the circumstances. Whenever nondisclosure of particular risk information is open to debate by reasonable-minded men, the issue is for the finder of the facts. 90

VI

Two exceptions to the general rule of disclosure have been noted by the courts. Each is in the nature of a physician’s privilege not to disclose, and the reasoning underlying them is appealing. Each, indeed, is but a recognition that, as important as is the patient’s right to know, it is greatly outweighed by the magnitudinous circumstances giving rise to the privilege. The first comes into play when the patient is unconscious or otherwise incapable of consenting, and harm from a failure to treat is imminent and outweighs any harm threatened by the proposed treatment. When a genuine emergency of that sort arises, it is settled that the impracticality of confer *789 ring with the patient dispenses with need for it. 91 Even in situations of that character the physician should, as current law requires, attempt to secure a relative’s consent if possible 92 But if time is too short to accommodate discussion, obviously the physician should proceed with the treatment. 93

The second exception obtains when risk-disclosure poses such a threat of detriment to the patient as to become unfeasible or contraindicated from a medical point of view. It is recognized that patients occasionally become so ill or emotionally distraught on disclosure as to foreclose a rational decision, or complicate or hinder the treatment, or perhaps even pose psychological damage to the patient. 94 Where that is so, the cases have generally held that the physician is armed with a privilege to keep the information from the patient, 95 and we think it clear that portents of that type may justify the physician in action he deems medically warranted. The critical inquiry is whether the physician responded to a sound medical judgment that communication of the risk information would present a threat to the patient’s well-being.

The physician’s privilege to withhold information for therapeutic reasons must be carefully circumscribed, however, for otherwise it might devour the disclosure rule itself. The privilege does not accept the paternalistic notion that the physician may remain silent simply because divulgence might prompt the patient to forego therapy the physician feels the patient really needs. 96 That attitude presumes instability or perversity for even the normal patient, and runs counter to the foundation principle that the patient should and ordinarily can make the choice for himself. 97 Nor does the privilege contemplate operation save where the patient’s reaction to risk information, as reasonable foreseen by the physician, is menacing. 98 And even in a situation of that kind, disclosure to a close relative with a view to securing consent to the proposed treatment may be the only alternative open to the physician. 99

*790 VII

No more than breach of any other legal duty does nonfulfillment of the physician’s obligation to disclose alone establish liability to the patient. An unrevealed risk that should have been made known must materialize, for otherwise the omission, however unpardonable, is legally without consequence. Occurrence of the risk must be harmful to the patient, for negligence unrelated to injury is nonaetionable. 100 And, as in malpractice actions generally, 101 there must be a causal relationship between the physician’s failure to adequately divulge and damage to the patient. 102

A causal connection exists when, but only when, disclosure of significant risks incidental to treatment would have resulted in a decision against it. 103 The patient obviously has no complaint if he would have submitted to the therapy notwithstanding awareness that the risk was one of its perils. On the other hand, the very purpose of the disclosure rule is to protect the patient against consequences which, if known, he would have avoided by foregoing the treatment. 104 The more difficult question is whether the factual issue on causality calls for an objective or a subjective determination.

It has been assumed that the issue is to be resolved according to whether the factfinder believes the patient’s testimony that he would not have agreed to the treatment if he had known of the danger which later ripened into injury. 105 We think a technique which ties the factual conclusion on causation simply to the assessment of the patient’s credibility is unsatisfactory. To be sure, the objective of risk-disclosure is preservation of the patient’s interest in intelligent self-choice on proposed treatment, a matter the patient is free to decide for any reason that appeals to him. 106 When, prior to commencement of therapy, the patient is sufficiently informed on risks and he exercises his choice, it may truly be said that he did exactly what he wanted to do. But when causality is explored at a post-injury trial with a professedly uninformed patient, the question whether he actually would have turned the treatment down if he had known the risks is purely hypothetical: “Viewed from the point at which he had to decide, would the patient have decided differently had he known something he did not know?” 107 And the answer which the patient supplies hardly represents more than a guess, perhaps tinged by the circumstance that the uncommunicated hazard has in fact materialized. 108

In our view, this method of dealing with the issue on causation comes in second-best. It places the physician in jeop *791 ardy of the patient’s hindsight and bitterness. It places the factfinder in the position of deciding whether a speculative answer to a hypothetical question is to be credited. It calls for a subjective determination solely on testimony of a patient-witness shadowed by the occurrence of the undisclosed risk. 109

Better it is, we believe, to resolve the causality issue on an objective basis: in terms of what a prudent person in the patient’s position would have decided if suitably informed of all perils bearing significance. 110 If adequate disclosw. could reasonably be expected to llave caused that person to decline the treatment because of the revelation of the kind of risk or danger that resulted in harm, causation is shown, but otherwise not. 111 The patient’s testimony is relevant on that score of course but it would not threaten to dominate the findings. And since that testimony would probably be appraised congruently with the factfinder’s belief in its reasonableness, the case for a wholly objective standard for passing on causation is strengthened. Such a standard would in any event ease the fact-finding process and better assure the truth as its product.

VIII

In the context of trial of a suit claiming inadequate disclosure of risk information by a physician, the patient has the burden of going forward with evidence tending to establish prima facie the essential elements of the cause of action, and ultimately the burden of proof — the risk of nonpersuasion 112 — on those elements. 113 These are normal impositions upon moving litigants, and no reason why they should not attach in nondisclosure cases is apparent. The burden of going forward with evidence pertaining to a privilege not to disclose, 114 however, rests properly upon the physician. This is not only because the patient has made out a prima facie case before an issue on privilege is reached, but also because any evidence bearing on the privilege is usually in the hands of the physician alone. Requiring him to open the proof on privilege is consistent with judicial policy laying such a burden on the party who seeks shelter from an exception to a general rule and who is more likely to have possession of the facts. 115

As in much malpractice litigation, 116 recovery in nondisclosure lawsuits has hinged upon the patient’s ability to prove through expert testimony that the physician’s performance departed from medical custom. This is not surprising since, as we have pointed out, the majority of American jurisdictions have limited the patient’s right to know to whatever boon can be found in medical practice. 117 We have already discussed our disagreement with the majority rationale. 118 We now delineate our view on the need for expert testimony in nondisclosure cases.

There are obviously important roles for medical testimony in such cases, and some roles which only medical evidence can fill: Experts are ordinarily indispensible to identify and elucidate for the factfinder the risks of therapy and *792 the consequences of leaving existing maladies untreated. They are normally needed on issues as to the cause of any injury or disability suffered by the patient and, where privileges are asserted, as to the existence of any emergency claimed and the nature and seriousness of any impact upon the patient from risk-disclosure. Save for relative infrequent instances where questions of this type are resolvable wholly within the realm of ordinary human knowledge and experience, the need for the expert is clear. 119

The guiding consideration our decisions distill, however, is that medical facts are for medical experts 120 and other facts are for any witnesses- — expert or not — having sufficient knowledge and capacity to testify to them. 121 It is evident that many of the issues typically involved in nondisclosure cases do not reside peculiarly within the medical domain. Lay witness testimony can competently establish a physician’s failure to disclose particular risk information, the patient’s lack of knowledge of the risk, and the adverse consequences following the treatment. 122 Experts are unnecessary to a showing of the materiality of a risk to a patient’s decision on treatment, or to the reasonably, expectable effect of risk disclosure on the decision. 123 These conspicuous examples of permissible uses of nonexpert testimony illustiv. the relative freedom of broad areas of the legij problem of risk nondisclosure from the demands for expert testimony that shackle plaintiffs’ other types of medical malpractice litigation. 124

*793 IX

We now confront the question whether appellant’s suit was barred, wholly or partly, by the statute of limitations. The statutory periods relevant to this inquiry are one year for battery actions 125 and three years for those charging negligence. 126 For one a minor when his cause of action accrues, they do not begin to run until he has attained his majority. 127 Appellant was nineteen years old when the laminectomy and related events occurred, and he filed his complaint roughly two years after he reached twenty-one. Consequently, any claim in suit subject to the one-year limitation came too late.

Appellant’s causes of action for the allegedly faulty laminectomy by Dr. Spence and allegedly careless post-operative care by the hospital present no problem. Quite obviously, each was grounded in negligence and so was governed by the three-year provision. 128 The duty-to-disclose claim appellant asserted against Dr. Spence, however, draws another consideration into the picture. We have previously observed that an unauthorized operation constitutes a battery, and that an uninformed consent to an operation does not confer the necessary authority. 129 If, therefore, appellant had at stake no more than a recovery of damages on account of a laminectomy intentionally done without intelligent permission, the statute would have interposed a bar.

It is evident, however, that appellant had much more at stake. 130 His interest in bodily integrity commanded protection, not only against an intentional invasion by an unauthorized operation 131 but also against a negligent invasion by his physician’s dereliction of duty to adequately disclose. 132 Appellant has asserted and litigated a violation of that duty throughout the case. 133 That claim, like the others, was governed by the three-year period of limitation applicable to negligence actions 134 and was *794 unaffected by the fact that its alternative was barred by the one-year period pertaining to batteries. 135

X

This brings us to the remaining question, common to all three causes of action: whether appellant’s evidence was of such caliber as to require a submission to the jury. On the first, the evidence was clearly sufficient to raise an issue as to whether Dr. Spence’s obligation to disclose information on risks was reassonably met or was excused by the surrounding circumstances. Appellant testified that Dr. Spence revealed to him nothing suggesting a hazard associated with the laminectomy. His mother testified that, in response to her specific inquiry, Dr. Spence informed her that the laminectomy was no more serious than any other operation. When, at trial, it developed from Dr. Spence’s testimony that paralysis can be expected in one percent of laminectomies, it became the jury’s responsibility to decide whether that peril was of sufficient magnitude to bring the disclosure duty into play. 136 There was no emergency to frustrate an opportunity to disclose, 137 and Dr. Spence’s expressed opinion that disclosure would have been unwise did not foreclose a contrary conclusion by the jury. There was no evidence that appellant’s emotional makeup was such that concealment of the risk of paralysis was medically sound. 138 Even if disclosure to appellant himself might have bred ill consequences, no reason appears for the omission to communicate the information to his mother, particularly in view of his minority. 139 The jury, not Dr. Spence, was the final arbiter of whether nondisclosure was reasonable under the circumstances. 140

Proceeding to the next cause of action, we find evidence generating issues as to whether Dr. Spence performed the laminectomy negligently and, if so, whether that negligence contributed causally to appellant’s subsequent disabilities. A report Dr. Spence prepared after the second operation indicated that at the time he felt that too-tight sutures at the laminectomy site might have caused the paralysis. While at trial Dr. Spence voiced the opinion that the sutures were not responsible, there were circumstances lending support to his original view. Prior to the laminectory, appellant had *795 none of the disabilities of which he now complains. The disabilities appeared almost immediately after the laminectomy. The gusset Dr. Spence made on the second operation left greater room for the spinal cord to pulsate, and this alleviated appellant’s condition somewhat. That Dr. Spence’s in-trial opinion was hardly the last word is manifest from the fact that the team of specialists consulting on appellant was unable to settle on the origin of the paralysis.

We are advertent to Dr. Spence’s attribution of appellant’s disabilities to his condition preexisting the laminectomy, but that was a matter for the jury. And even if the jury had found that theory acceptable, there would have remained the question whether Dr. Spence aggravated the preexisting condition. A tortfeasor takes his victim as he finds him, and negligence intensifying an old condition creates liability just as surely as negligence precipitating a new one. 141 It was for the jury to say, on the whole evidence, just what contributions appellant’s preexisting condition and Dr. Spence’s medical treatment respectively made to the disabilities.

In sum, judged by legal standards, the proof militated against a directed verdict in Dr. Spence’s favor. True it is that the evidence did not furnish ready answers on the dispositive factual issues, but the important consideration is that appellant showed enough to call for resolution of those issues by the jury. As in Sentilles v. Inter-Carribbean Shipping Corporation, 142 a case resembling this one, the Supreme Court stated,

The jury’s power to draw the inference that the aggravation of petitioner’s tubercular condition, evident so shortly after the accident, was in fact caused by that accident, was not impaired by the failure of any medical witness to testify that it was in fact the cause. Neither can it be impaired by the lack of medical unanimity as to the respective likelihood of the potential causes of the aggravation, or by the fact that other potential causes of aggravation existed and were not conclusively negated by the proofs. The matter does not turn on the use of a particular form of words by the physicians in giving their testimony. The members of the jury, not the medical witnesses, were sworn to make a legal determination of the question of causation. They were entitled to take all the circumstances, including the medical testimony into consideration. 143

We conclude, lastly, that the case against the hospital should also have gone to the jury. The circumstances surrounding appellant’s fall — the change in Dr. Spence’s order that appellant be kept in bed, 144 the failure to maintain a side rail on appellant’s bed, and the absence of any attendant while appellant was attempting to relieve himself — could certainly suggest to jurors a dereliction of the hospital’s duty to exercise reasonable care for the safety and well-being of the patient. 145 On the issue of causality, the *796 evidence was uneontradicted that appellant progressed after the operation until the fall but, a few hours thereafter, his condition had deteriorated, and there were complaints of paralysis and respiratory difficulty. That falls tend to cause or aggravate injuries is, of course, common knowledge, which in our view the jury was at liberty to utilize. 146 To this may be added Dr. Spence’s testimony that paralysis can be brought on by trauma or shock. All told, the jury had available a store of information enabling an intelligent resolution of the issues respecting the hospital. 147

We realize that, when appellant rested his case in chief, the evidence scarcely served to put the blame for appellant’s disabilities squarely on one appellee or the other. But this does not mean that either could escape liability at the hand of the jury simply because appellant was unable to do more. As ever so recently we ruled, “a showing of negligence by each of two (or more) defendants with uncertainty as to which caused the harm does not defeat recovery but passes the burden to the tortfeasors for each to prove, if he can, that he did not cause the harm.” 148 In the case before us, appellant’s evidentiary presentation on negligence survived the claims of legal insufficiency, and appellees should have been put to their proof. 149

Reversed and remanded for a new trial.

Opinion

ARABIAN, J.

A physician’s duty to disclose to a patient information material to the decision whether to undergo treatment is the central constituent of the legal doctrine known as “informed consent.” In this case, we *1176 review the ruling of a divided Court of Appeal that, in recommending a course of chemotherapy and radiation treatment to a patient suffering from a virulent form of cancer, the treating physicians breached their duty to obtain the patient’s informed consent by failing to disclose his statistical life expectancy.

As will appear, we conclude that the Court of Appeal erred in reaching that result. We also conclude that the court erred in holding that an instruction routinely given in informed consent cases fails to convey accurately to the jury the legal standard governing its evaluation of the sufficiency of the disclosures actually made by physician to patient. We hold in addition that the Court of Appeal erred in suggesting, as it appeared to do, that under the doctrine of informed consent, a physician is under a duty to disclose information material to the patient’s nonmedical interests. Finally, because the propriety of disclosing statistical life expectancy information to a cancer patient depends on the standard of practice within the medical community, we conclude that expert testimony was properly admitted by the trial court for that limited purpose.

I

A

Mildos Arato was a successful 42-year-old electrical contractor and part-time real estate developer when, early in 1980, his internist diagnosed a failing kidney. On July 21, 1980, in the course of surgery to remove the kidney, the operating surgeon detected a tumor on the “tail” or distal portion of Mr. Arato’s pancreas. After Mrs. Arato gave her consent, portions of the pancreas were resected, or removed, along with the spleen and the diseased kidney. A follow-up pathological examination of the resected pancreatic tissue confirmed a malignancy. Concerned that the cancer could recur and might have infiltrated adjacent organs, Mr. Arato’s surgeon referred him to a group of oncology practitioners for follow-up treatment.

During his initial visit to the oncologists, Mr. Arato filled out a multipage questionnaire routinely given new patients. Among the some 150 questions asked was whether patients “wish[ed] to be told the truth about [their] condition” or whether they wanted the physician to “bear the burden” for them. Mr. Arato checked the box indicating that he wished to be told the truth.

The oncologists discussed with Mr. and Mrs. Arato the advisability of a course of chemotherapy known as “F.A.M.,” a treatment employing a combination of drugs which, when used in conjunction with radiation therapy, *1177 had shown promise in treating pancreatic cancer in experimental trials. The nature of the discussions between Mr. and Mrs. Arato and the treating physicians, and in particular the scope of the disclosures made to the patient by his doctors, was the subject of conflicting testimony at trial. By their own admission, however, neither the operating surgeon nor the treating oncologists specifically disclosed to the patient or his wife the high statistical mortality rate associated with pancreatic cancer.

Mr. Arato’s oncologists determined that a course of F.A.M. chemotherapy was indicated for several reasons. According to their testimony, the high statistical mortality of pancreatic cancer is in part a function of what is by far the most common diagnostic scenario—the discovery of the malignancy well after it has metastasized to distant sites, spreading throughout the patient’s body. As noted, in Mr. Arato’s case, the tumor was comparatively localized, having been discovered in the tail of the pancreas by chance in the course of surgery to remove the diseased kidney.

Related to the “silent” character of pancreatic cancer is the fact that detection in such an advanced state usually means that the tumor cannot as a practical matter be removed, contributing to the high mortality rate. In Mr. Arato’s case, however, the operating surgeon determined that it was possible to excise cleanly the tumorous portion of the pancreas and to leave a margin of about one-half centimeter around the surgical site, a margin that appeared clinically to be clear of cancer cells. Third, the mortality rate is somewhat lower, according to defense testimony, for pancreatic tumors located in the distal part of the organ than for those found in the main body. Finally, then-recent experimental studies on the use of F.A.M. chemotherapy in conjunction with therapeutic radiation treatments had shown promising response rates—on the order of several months of extended life—among pancreatic cancer patients.

Mr. Arato’s treating physicians justified not disclosing statistical life expectancy data to their patient on disparate grounds. According to the testimony of his surgeon, Mr. Arato had exhibited great anxiety over his condition, so much so that his surgeon determined that it would have been medically inappropriate to disclose specific mortality rates. The patient’s oncologists had a somewhat different explanation. As Dr. Melvin Avedon, his chief oncologist, put it, he believed that cancer patients in Mr. Arato’s position “wanted to be told the truth, but did not want a cold shower.” Along with the other treating physicians, Dr. Avedon testified that in his opinion, the direct and specific disclosure of extremely high mortality rates for malignancies such as pancreatic cancer might effectively deprive a patient of any hope of cure, a medically inadvisable state. Moreover, all of the treating *1178 physicians testified that statistical life expectancy data had little predictive value when applied to a particular patient with individualized symptoms, medical history, character traits and other variables.

According to the physicians’ testimony, Mr. and Mrs. Arato were told at the outset of the treatment that most victims of pancreatic cancer die of the disease, that Mr. Arato was at “serious” or “great” risk of a recurrence and that, should the cancer return, his condition would be judged incurable. This information was given to the patient and his wife in the context of a series of verbal and behavioral cues designed to invite the patient or family member to follow up with more direct and difficult questions. Such follow-up questions, on the order of “how long do I have to live?,” would have signaled to his doctors, according to Dr. Avedon’s testimony, the patient’s desire and ability to confront the fact of imminent mortality. In the judgment of his chief oncologist, Mr. Arato, although keenly interested in the clinical significance of the most minute symptom, studiously avoided confronting these ultimate issues; according to his doctors, neither Mr. Arato nor his wife ever asked for information concerning his life expectancy in more than 70 visits over a period of a year. Believing that they had disclosed information sufficient to enable him to make an informed decision whether to undergo chemotherapy, Mr. Arato’s doctors concluded that their patient had as much information regarding his condition and prognosis as he wished.

Dr. Avedon also testified that he told Mr. Arato that the effectiveness of F.A.M. therapy was unproven in cases such as his, described its principal adverse side effects, and noted that one of the patient’s options was not to undergo the treatment. In the event, Mr. Arato consented to the proposed course of chemotherapy and radiation, treatments that are prolonged, difficult and painful for cancer patients. Unfortunately, the treatment proved ineffective in arresting the spread of the malignancy. Although clinical tests showed him to be free of cancer in the several months following the beginning of the F.A.M. treatments, beginning in late March and into April of 1981, the clinical signs took an adverse turn. 1 By late April, the doctors were convinced by the results of additional tests that the cancer had returned and was spreading. They advised the patient of their suspicions and discontinued chemotherapy. On July 25, 1981, a year and four days following surgery, Mr. Arato succumbed to the effects of pancreatic cancer.

*1179 B

Not long after his death, Mr. Arato’s wife and two children brought this suit against the physicians who had treated their husband and father in his last days, including the surgeon who performed the pancreas resection and the oncologists who had recommended and administered the chemotherapy/ radiation treatment. As presented to the jury, 2 the gist of the lawsuit was the claim that in discussing with their patient the advisability of undergoing a course of chemotherapy and radiation, Mr. Arato’s doctors had failed to disclose adequately the shortcomings of the proposed treatment in light of the diagnosis, and thus had failed to obtain the patient’s informed consent. Specifically, plaintiffs contended that the doctors were aware that, because early detection is difficult and rare, pancreatic cancer is an especially virulent malignancy, one in which only 5 to 10 percent of those afflicted live for as long as five years, and that given the practically incurable nature of the disease, there was little chance Mr. Arato would live more than a short while, even if the proposed treatment proved effective.

Such mortality information, the complaint alleged—especially the statistical morbidity rate of pancreatic cancer—was material to Mr. Arato’s decision whether to undergo postoperative treatment; had he known the bleak truth concerning his life expectancy, he would not have undergone the rigors of an unproven therapy, but would have chosen to live out his last days at peace with his wife and children, and arranging his business affairs. Instead, the complaint asserted, in the false hope that radiation and chemotherapy treatments could effect a cure—a hope born of the negligent failure of his physicians to disclose the probability of an early death—Mr. Arato failed to order his affairs in contemplation of his death, an omission that, according to the complaint, led eventually to the failure of his contracting business and to substantial real estate and tax losses following his death.

As the trial neared its conclusion and the court prepared to charge the jury, plaintiffs requested that several special instructions be given relating to the nature and scope of the physician’s duty of disclosure. Two proffered instructions in particular are pertinent to this appeal. In the first, plaintiffs asked the trial court to instruct the jury that “A physician has a fiduciary duty to a patient to make a full and fair disclosure to the patient of all facts which materially affect the patient’s rights and interests.” The second instruction sought by plaintiffs stated that “The scope of the physician’s duty *1180 to disclose is measured by the amount of knowledge a patient needs in order to make an informed choice. All information material to the patient’s decision should be given.”

The trial judge declined to give the jury either of the two instructions sought by plaintiffs. Instead, the court read to the jury a modified version of BAJI No. 6.11, the so-called “reality of consent” instruction drawn from our opinion in Cobbs v. Grant (1972) 8 Cal.3d 229 [104 Cal.Rptr. 505, 502 P.2d 1]. As can be seen by a comparison of the two instructions, the texts of which are set out in the margin, 3 the instruction actually given the jury by the trial court substantially recapitulated the wording of BAJI No. 6.11, *1181 except for the omission of two brief paragraphs dealing with exceptions to the duty of disclosure and a third paragraph that appears on its face not to have been relevant to the case as it developed at trial.

In addition to the modified version of BAJI No. 6.11, the trial court supplemented its informed consent instructions to the jury with the three special instructions, two requested by plaintiffs and a third offered by defendants, set out below. 4 Finally, with plaintiffs’ approval, the trial court gave the jury several generic BAJI instructions dealing with such topics as the general legal duties of physicians and specialists (BAJI Nos. 6.00 & 6.11), the negligence standard of care in medical cases (BAJI Nos. 6.02 & 6.30) and when patient consent is necessary (BAJI No. 6.10).

After concluding its deliberations, the jury returned two special verdicts —on a form approved by plaintiffs’ counsel—finding that none of the defendants was negligent in the “medical management” of Mr. Arato, and that defendants “disclosed to Mr. Arato all relevant information which would have enabled him to make an informed decision regarding the proposed treatment to be rendered him.” Plaintiffs appealed from the judgment entered on the defense verdict, contending that the trial court erred in refusing to give the jury the special instructions requested by them. As noted, a divided Court of Appeal reversed the judgment of the trial court, and ordered a new trial. We granted defendants’ ensuing petition for review and now reverse the judgment of the Court of Appeal.

C

In the Court of Appeal’s view, Mr. Arato’s doctors had breached the duty to disclose to their patient information material to the decision whether to undergo the radiation and drug therapy. According to the Court of Appeal, because there are so many different cancers, the lethality of which varies dramatically, telling a patient that cancer might recur and would then be *1182 incurable, without providing at least some general information concerning the virulence of the particular cancer at issue as reflected in mortality tables, was “meaningless.” In addition, the Court of Appeal reasoned that his physicians were under a duty to disclose numerical life expectancy information to Mr. Arato so that he and his wife might take timely measures to minimize or avoid the risks of financial loss resulting from his death.

The Court of Appeal also concluded that the instructions concerning the physicians’ duty of disclosure given the jury by the trial judge were defective in two respects. First, one paragraph of BAJI No. 6.11 improperly emphasized a physician’s defense to a failure-to-disclose claim as well as the importance of community medical standards in measuring the adequacy of the disclosures. These defects would have been mitigated by giving the jury plaintiffs’ requested instructions, the court reasoned.

In addition, the Court of Appeal concluded that the instruction, given at the request of the defendants, to the effect that the primary duty of a physician is “to do what is best for his patient,” operated to mislead the jury into believing that a physician’s duty of disclosure may be limited by his or her own opinion as to what is in the patient’s best interests. The Court of Appeal also concluded that the jury was misled as to the governing legal standard by the fact that the specific disclosure instructions modeled on BAJI No. 6.11 were preceded by other, lengthy instructions from BAJI (BAJI Nos. 6.00, 6.01, 6.02, 6.03, 6.30 [7th ed. 1986 bound vol.]) dealing with the general standard of care for medical professionals in negligence actions —an ordering that, the court reasoned, compounded the skewed impression already conveyed to the jury regarding the significance of community medical standards in informed consent cases.

Finally, the Court of Appeal concluded that the trial court had erred in permitting defendants to introduce the testimony of expert medical witnesses. Although conceding that expert testimony is appropriate where the physician’s defense rests on the so-called “therapeutic exception” (e.g., that the patient was emotionally incapable of making a rational decision concerning a proposed treatment), the court reasoned that the expert defense testimony permitted by the trial court went well beyond that narrow exception to the duty of disclosure, misleading the jury in their deliberations regarding the significance of community medical practice and prejudicing plaintiffs’ case.

II

A

The fount of the doctrine of informed consent in California is our decision of some 20 years ago in Cobbs v. Grant, supra, 8 Cal.3d 229, an opinion by *1183 a unanimous court that built on several out-of-state decisions significantly broadening the scope and character of the physician’s duty of disclosure in obtaining the patient’s consent to treatment. 5 In Cobbs v. Grant, we not only anchored much of the doctrine of informed consent in a theory of negligence liability, but also laid down four “postulates” as the foundation on which the physician’s duty of disclosure rests.

“The first [of these postulates,]” we wrote, “is that patients are generally persons unlearned in the medical sciences and therefore, except in rare cases, courts may safely assume the knowledge of patient and physician are not in parity. The second is that a person of adult years and in sound mind has the right, in the exercise of control over his own body, to determine whether or not to submit to lawful medical treatment.” (8 Cal.3d at p. 242.)

“The third [postulate,]” we continued, “is that the patient’s consent to treatment, to be effective, must be an informed consent. And the fourth is that the patient, being unlearned in medical sciences, has an abject dependence upon and trust in his physician for the information upon which he relies during the decisional process, thus raising an obligation in the physician that transcends arms-length transactions.” (8 Cal.3d at p. 242.) From these ethical imperatives, we derived the obligation of a treating physician “of reasonable disclosure of the available choices with respect to proposed therapy and of the dangers inherently and potentially involved in each.” (8 Cal.3d at p. 243.)

Since Cobbs v. Grant, supra, 8 Cal.3d 229, was decided, we have revisited the doctrine of informed consent. In Truman v. Thomas (1980) 27 Cal.3d 285 [165 Cal.Rptr. 308, 611 P.2d 902], we held that the physician’s duty of due care embraced disclosure of the material risks resulting from the patient’s refusal to consent to a recommended treatment—in that case, a routine annual pap smear. In concluding that the trial court had erred reversibly in refusing to instruct the jury on the'physician’s duty of disclosure, we said that the doctrine of informed consent recognized in Cobbs v. Grant, supra, 8 Cal.3d 229, was imposed “so that patients might meaningfully exercise their right to make decisions about their own bodies.” (Truman v. Thomas, supra, at p. 292.)

*1184 Our opinion also stressed the paramount role of the trier of fact in informed consent cases. We recognized, for example, that questions such as whether the danger posed by a failure to disclose a particular risk is remote, whether the risk was or was not commonly known, and whether circumstances unique to a given case supported a duty of disclosure were matters for the jury to decide. We accordingly declined to hold that as a matter of law the physician owed no duty to make a given disclosure to the patient. That question, we concluded, was one for the jury to decide. (Truman v. Thomas, supra, 27 Cal.3d at pp. 293-294.)

We recently returned to the scope of a physician’s duty of disclosure in Moore v. Regents of University of California (1990) 51 Cal.3d 120 [271 Cal.Rptr. 146, 793 P.2d 479, A.L.R.4th 3659] (Moore). Although the chief focus of Moore was whether the nonconsensual use of human cells in medical research supported a patient’s action seeking to impose on health professionals liability for conversion, our opinion reaffirmed the “well-established principles” enunciated in Cobbs v. Grant, supra, 8 Cal.3d 229. (51 Cal.3d at p. 129.) It was on that foundation that we held “a physician must disclose personal interests unrelated to the patient’s health, whether research or economic, that may affect the physician’s personal judgment . . . .” (Ibid.)

B

Together with companion decisions in other jurisdictions, Cobbs v. Grant, supra, 8 Cal.3d 229, is one of the epochal opinions in the legal recognition of the medical patient’s protectible interest in autonomous decisionmaking. After more than a generation of experience with the judicially broadened duty of physician disclosure, the accumulated medicolegal comment on the subject of informed consent is both large and discordant. Those critics writing under the banner of “patient autonomy” insist that the practical administration of the doctrine has been thwarted by a failure of judicial nerve and an unremitting hostility to its underlying spirit by the medical profession. Others, equally earnest, assert that the doctrine misapprehends the realities of patient care and enshrines moral ideals in the place of workable rules. 6

Despite the critical standoff between these extremes of “patient sovereignty” and “medical paternalism,” indications are that the Cobbs-era *1185 decisions helped effect a revolution in attitudes among patients and physicians alike regarding the desirability of frank and open disclosure of relevant medical information. 7 The principal question we must address is whether our holding in Cobbs v. Grant, supra, 8 Cal.3d 229, as embodied in BAJI No. 6.11, accurately conveys to juries the legal standard under which they assess the evidence in determining the adequacy of the disclosures made by physician to patient in a particular case or whether, as the Court of Appeal here appeared to conclude, the standard instruction should be revised to mandate specific disclosures such as patient life expectancy as revealed by mortality statistics.

In our view, one of the merits of the somewhat abstract formulation of BAJI No. 6.11 is its recognition of the importance of the overall medical context that juries ought to take into account in deciding whether a challenged disclosure was reasonably sufficient to convey to the patient information material to an informed treatment decision. The contexts and clinical settings in which physician and patient interact and exchange information material to therapeutic decisions are so multifarious, the informational needs and degree of dependency of individual patients so various, and the professional relationship itself such an intimate and irreducibly judgment-laden one, that we believe it is unwise to require as a matter of law that a particular species of information be disclosed. We agree with the insight in Salgo, supra, 154 Cal.App.2d at page 578, that in administering the doctrine of informed consent, “each patient presents a separate problem, that the patient’s mental and emotional condition is important and in certain cases may be crucial, and that in discussing the element of risk a certain amount of discretion must be employed consistent with the full disclosure of facts necessary to an informed consent.”

Our opinion in Cobbs v. Grant, supra, 8 Cal.3d 229, recognized these “common practicalities” of medical treatment which, we said, make the ideal *1186 of “full disclosure” a “facile expression[].” (Id. at p. 244.) Eschewing both a “minicourse in medical science” and a duty to discuss “the relatively minor risks inherent in common procedures,” we identified the touchstone of the physician’s duty of disclosure in the patient’s need for “adequate information to enable an intelligent choice,” a peculiarly fact-bound assessment which juries are especially well-suited to make. (Id. at pp. 244-245.)

This sensitivity to context seems all the more appropriate in the case of life expectancy projections for cancer patients based on statistical samples. Without exception, the testimony of every physician-witness at trial confirmed what is evident even to a nonprofessional: statistical morbidity values derived from the experience of population groups are inherently unreliable and offer little assurance regarding the fate of the individual patient; indeed, to assume that such data are conclusive in themselves smacks of a refusal to explore treatment alternatives and the medical abdication of the patient’s well-being. Certainly the jury here heard evidence of articulable grounds for the conclusion that the particular features of Mr. Arato’s case distinguished it from the typical population of pancreatic cancer sufferers and their dismal statistical probabilities—a fact plaintiffs impliedly acknowledged at trial in conceding that the oncologic referral of Mr. Arato and ensuing chemotherapy were not in themselves medically negligent.

In declining to endorse the mandatory disclosure of life expectancy probabilities, we do not mean to signal a retreat from the patient-based standard of disclosure explicitly adopted in Cobbs v. Grant, supra, 8 Cal.3d 229, 243. We reaffirm the view taken in Cobbs that, because the “weighing of these risks [i.e., those inherent in a proposed procedure] against the individual subjective fears and hopes of the patient is not an expert skill,” the test “for determining whether a potential peril must be divulged is its materiality to the patient’s decision.” (Id. at pp. 243, 245.) In reaffirming the appropriateness of that standard, we can conceive of no trier of fact more suitable than lay jurors to pronounce judgment on those uniquely human and necessarily situational ingredients that contribute to a specific doctor-patient exchange of information relevant to treatment decisions; certainly this is not territory in which appellate courts can usefully issue “bright line” guides.

Rather than mandate the disclosure of specific information as a matter of law, the better rule is to instruct the jury that a physician is under a legal duty to disclose to the patient all material information—that is, “information which the physician knows or should know would be regarded as significant by a reasonable person in the patient’s position when deciding to accept or reject a recommended medical procedure”—needed to make an informed decision regarding a proposed treatment. That, of course, is the formulation *1187 embodied in BAJI No. 6.11 and the instruction given in this case. Having been properly instructed, the jury returned a defense verdict—on a form approved by plaintiffs’ counsel—specifically finding that defendants had “disclosed to Mr. Arato all relevant information which would have enabled him to make an informed decision regarding the proposed treatment to be rendered him.”

We decline to intrude further, either on the subtleties of the physician-patient relationship or in the resolution of claims that the physician’s duty of disclosure was breached, by requiring the disclosure of information that may or may not be indicated in a given treatment context. Instead, we leave the ultimate judgment as to the factual adequacy of a challenged disclosure to the venerable American jury, operating under legal instructions such as those given here and subject to the persuasive force of trial advocacy.

Here, the evidence was more than sufficient to support the jury’s finding that defendants had reasonably disclosed to Mr. Arato information material to his decision whether to undergo the proposed chemotherapy/radiation treatment. There was testimony that Mr. and Mrs. Arato were informed that cancer of the pancreas is usually fatal; of the substantial risk of recurrence, an event that would mean his illness was incurable; of the unproven nature of the F.A.M. treatments and their principal side effects; and of the option of forgoing such treatments. Mr. Arato’s doctors also testified that they could not with confidence predict how long the patient might live, notwithstanding statistical mortality tables.

In addition, the jury heard testimony regarding the patient’s apparent avoidance of issues bearing upon mortality; Mrs. Arato’s testimony that his physicians had assured her husband that he was “clear” of cancer; and the couple’s common expectation that he had been “cured,” only to learn, suddenly and unexpectedly, that the case was hopeless and life measurable in weeks. The informed consent instructions given the jury to assess this evidence were an accurate statement of the law, and the Court of Appeal in effect invaded the province of the trier of fact in overturning a fairly litigated verdict. 8

*1188 c

In addition to their claim that his physicians were required to disclose statistical life expectancy data to Mr. Arato to enable him to reach an informed treatment decision, plaintiffs also contend that defendants should have disclosed such data because it was material to the patient’s nonmedical interests, that is, Mr. Arato’s business and investment affairs and the potential adverse impact of his death upon them. In support of this proposition, plaintiffs rely on the following statement in Bowman v. McPheeters (1947) 77 Cal.App.2d 795, 800 [176 P.2d 745]: “As fiduciaries it was the duty of defendants [physicians] to make a full and fair disclosure to plaintiff of all facts which materially affected his rights and interests.” Plaintiffs contend that since Mr. Arato’s contracting and real estate affairs would suffer if he failed to make timely changes in estate planning in contemplation of imminent death, and since these matters are among “his rights and interests,” his physicians were under a legal duty to disclose all material facts that might affect them, including statistical life expectancy information. We reject the claim as one founded on a premise that is not recognized in California.

The short answer to plaintiffs’ claim is our statement in Moore, supra, 51 Cal.3d 120, that a “physician is not the patient’s financial adviser.” (Id. at p. 131, fn. 10.) From its inception, the rationale behind the disclosure requirement implementing the doctrine of informed consent has been to protect the patient’s freedom to “exercise . . . control over [one’s] own body” by directing the course of medical treatment. (Cobbs v. Grant, supra, 8 Cal.3d at p. 242.) We recently noted that ‘the principle of self-determination . . . embraces all aspects of medical decisionmaking by the competent adult . . . .” (Thor v. Superior Court, supra, 5 Cal.4th 725, 738.) Although an aspect of personal autonomy, the conditions for the exercise of the patient’s right of self-decision presuppose a therapeutic focus, a supposition reflected in the text of BAJI No. 6.11 itself. 9 The fact that a physician has “fiducial” obligations (Cobbs v. Grant, supra, 8 Cal.3d at p. 246) which, as the result in *1189 Bowman illustrates, prohibit misrepresenting the nature of the patient’s medical condition, does not mean that he or she is under a duty, the scope of which is undefined, to disclose every contingency that might affect the patient’s nonmedical “rights and interests.” 10 Because plaintiffs’ open-ended proposed instruction—that the physician’s duty embraces the “disclosure ... of all facts which materially affect the patient’s rights and interests”—failed to reflect the therapeutic limitation inherent in the doctrine of informed consent, it would have been error for the trial judge to give it to the jury. 11

Finally, plaintiffs make much of the fact that in his initial visit to Dr. Avedon’s office, Mr. Arato indicated in a lengthy form he was requested to complete that he “wish[ed] to be told the truth about [his] condition.” In effect, they contend that as a result of Mr. Arato’s affirmative answer, defendants had an absolute duty to make specific life expectancy disclosures to him. Whether the patient has filled out a questionnaire indicating that he or she wishes to be told the “truth” about his of her condition or not, however, a physician is under a legal duty to obtain the patient’s informed consent to any recommended treatment. Although a patient may validly waive the right to be informed, we do not see how a request to be told the “truth” in itself heightens the duty of disclosure imposed on physicians as a matter of law.

*1190 III

The final issue we must resolve concerns the use of expert testimony at trial. As noted, the Court of Appeal concluded that expert testimony offered on behalf of defendants went beyond what was appropriate in support of the so-called “therapeutic exception” to the physician’s duty of disclosure, misleading the jury and prejudicing plaintiffs’ case. Resolution of this issue requires an understanding of the proper, albeit limited, role of expert testimony in informed consent cases.

Over plaintiffs’ objection, the trial court admitted the testimony of two medical experts, Drs. Plotkin and Wellisch, the former a professor of clinical medicine and the latter an expert in the psychological management of cancer patients. Both testified that the standard of medical practice cautioned against disclosing to pancreatic cancer patients specific life expectancy data unless the patient directly requested such information and that, in effect, defendants complied with that standard in not disclosing such information to Mr. Arato under the circumstances. Plaintiffs offered expert medical testimony of their own to counter this evidence; their expert testified that there are a number of indirect and compassionate ways to approach the issue of imminent mortality in dealing with patients with terminal cancer and that the standard of professional practice required that a patient in Mr. Arato’s circumstances be given specific numerical life expectancy information.

Plaintiffs now complain that it was error for the trial court to admit expert defense testimony, relying on our statement in Cobbs v. Grant, supra, 8 Cal.3d at page 243, that the weighing of the risks accompanying a given therapy “against the individual subjective fears and hopes of the patient is not an expert skill.” Plaintiffs fail to distinguish between the two kinds of physician disclosure discussed in Cobbs. Our formulation of the scope of the duty of disclosure encompassed “the potential of death or serious harm” known to be inherent in a given procedure and an explanation “in lay terms [of] the complications that might possibly occur.” (Id., at p. 244.) In addition to these disclosures, which we termed the “minimal” ones required of a physician to insure the patient’s informed decisionmaking, we said that the physician must also reveal to the patient “such additional information as a skilled practitioner of good standing would provide under similar circumstances.” (Id. at pp. 244-245.)

As its verbatim presence in BAJI No. 6.11 testifies, the quoted language, including the reference to the standard of professional practice as the benchmark for measuring the scope of disclosure beyond that implicated by the risks of death or serious harm and the potential for complications, has *1191 become an integral part of the legal standard in California for measuring the adequacy of a physician’s disclosure in informed consent cases. (See, e.g., Vandi v. Permanente Medical Group. Inc., supra, 7 Cal.App.4th 1064, 1071; Mathis v. Morrissey, supra, 11 Cal.App.4th 332, 344; Morgenroth v. Pacific Medical Center, Inc. (1976) 54 Cal.App.3d 521, 534-535 [126 Cal.Rptr. 681].)

In reckoning the scope of disclosure, the physician will for the most part be guided by the patient’s decisional needs—or, as we said in Cobbs v. Grant, supra, “the test for determining whether a potential peril must be divulged is its materiality to the patient’s decision.” (8 Cal.3d at p. 245.) A physician, however, evaluates the patient’s decisional needs against a background of professional understanding that includes a knowledge of what information beyond the significant risks associated with a given treatment would be regarded by the medical community as appropriate for disclosure under the circumstances.

It is thus evident that under the formulation we adopted in Cobbs v. Grant, supra, 8 Cal.3d 229, situations will sometimes arise in which the trier of fact is unable to decide the ultimate issue of the adequacy of a particular disclosure without an understanding of the standard of practice within the relevant medical community. For that reason, in an appropriate case, the testimony of medical experts qualified to offer an opinion regarding what, if any, disclosures—in addition to those relating to the risk of death or serious injury and significant potential complications posed by consenting to or declining a proposed treatment—would be made to the patient by a skilled practitioner in the relevant medical community under the circumstances, is relevant and admissible.

We underline the limited and essentially subsidiary role of expert testimony in informed consent litigation. As we cautioned in Cobbs v. Grant, supra, 8 Cal.3d 229, a rule that filters the scope of patient disclosure entirely through the standards of the medical community “ ‘arrogate[s] the decision [of what to disclose] ... to the physician alone.’ ” (Id. at p. 243.) We explicitly rejected such an absolute rule as inimical to the rationale and objectives of the informed consent doctrine; we reaffirm that position. Nevertheless, as explained above, there may be a limited number of occasions in the trial of informed consent claims where the adequacy of disclosure in a given case may turn on the standard of practice within the relevant medical community. In such instances, expert testimony will usually be appropriate.

Because statistical life expectancy data is information that lies outside the significant risks associated with a given treatment, the disclosure of which is *1192 mandated by Cobbs v. Grant, supra, 8 Cal.3d 229, it falls within the scope of the “additional information ... a skilled practitioner . . . would provide . . . .” (Id. at pp. 244-245.) And since the question of whether a physician should disclose such information turns on the standard of practice within the medical community, the trial court did not err in permitting expert testimony directed at that issue.

Finally, plaintiffs complain that a statement included in a special instruction given at defendants’ request—that “the primary duty of a physician is to do what is best for his patient”—was reversible error. We disagree. Although the challenged language is clearly a misstatement of governing law and should not have been given by the trial court, it is unlikely that these dozen or so words, appearing late in the mass of instructions, could have operated to mislead the jurors into believing that Mr. Arato’s doctors were legally free to tell him as much or as little as they wished. Although it was error to read to the jury defendants’ special instruction as drafted, it was not prejudicial under the circumstances. 12

Conclusion

The judgment of the Court of Appeal is reversed and the cause is remanded with directions to affirm the judgment of the trial court.

Lucas, C. J., Mosk, J., Panelli, J., Kennard, J., Baxter, J., and George, J., concurred.

SPOTTSWOOD W. ROBINSON, III, Circuit Judge:

This appeal is from a judgment entered in the District Court on verdicts directed for the two appellees at the conclusion of plaintiff-appellant Canterbury’s case in chief. His action sought damages for personal injuries allegedly sustained as a result of an operation negligently performed by appellee Spence, a negligent failure by Dr. Spence to disclose a risk of serious disability inherent in the operation, and negligent post-operative care by appellee Washington Hospital Center. On close examination of the record, we find evidence which required submission of these issues to the jury. We accordingly reverse the judgment as to each appellee and remand the case to the District Court for a new trial.

I

The record we review tells a depressing tale. A youth troubled only by back pain submitted to an operation without being informed of a risk of paralysis incidental thereto. A day after the operation he fell from his hospital bed after having been left without assistance while voiding. A few hours after the fall, the lower half of his body was paralyzed, and he had to be operated on again. Despite extensive medical care, he has never been what he was before. Instead of the back pain, even years later, he hobbled about on crutches, a vietim of paralysis of the bowels and urinary incontinence. In a very real sense this lawsuit is an understandable search for reasons.

At the time of the events which gave rise to this litigation, appellant was nineteen years of age, a clerk-typist employed by the Federal Bureau of Investigation. In December, 1958, he began to experience severe pain between his shoulder blades. 1 He consulted two general practitioners, but the medications they prescribed failed to eliminate the pain. Thereafter, appellant secured an appointment with Dr. Spence, who is a neurosurgeon.

Dr. Spence examined appellant in his office at some length but found nothing amiss. • On Dr. Spence’s advice appellant was x-rayed, but the films did not identify any abormality. Dr. Spence then recommended that appellant undergo a myelogram — a procedure in which dye is injected into the spinal column and traced to find evidence of disease or other disorder — at the Washington Hospital Center.

Appellant entered the hospital on February 4, 1959. 2 Thg myelogram revealed a “filling defect” in the region of the fourth thoracic vertebra. Since a myelogram often does no more than pinpoint *777 the location of an aberration, surgery may be necessary to discover the cause. Dr. Spence told appellant that he would have to undergo a laminectomy — -the excision of the posterior arch of the vertebra — to correct what he suspected was a ruptured disc. Appellant did not raise"! any objection to the proposed operation nor did he probe into its exact nature.

Appellant explained to Dr. Spence that his mother was a widow of slender financial means living in Cyclone, West Virginia, and that she could be reached through a neighbor’s telephone. Appellant called-his mother the day after the myelogram was performed and, failing to contact her, left Dr. Spence’s telephone number with the neighbor. When Mrs. Canterbury returned the call, Dr. Spence told her that the surgery was occasioned by a suspected ruptured disc. Mrs. Canterbury then asked if the recommended-operation was serious and Dr. Spence replied “not anymore than any other operation.” He added that he knew Mrs. Canterbury was not well off and that her presence in Washington would not be necessary. The testimony is contradictory as to whether during the course of the conversation Mrs. Canterbury expressed her consent to the operation. Ap pellant himself apparently did not converse again with Dr. Spence prior to the operation.

Dr. Spence performed the laminectomy on February 11 3 at the Washington Hospital Center. Mrs. Canterbury traveled to Washington, arriving on that date but after the operation was over, and signed a consent-form at .the hospital. The laminectomy revealed several anomalies : a spinal cord that was swollen and unable to pulsate, an accumulation of large tortuous and dilated veins, and a complete absence of epidural fat which normally surrounds the spine. A thin hypodermic needle was inserted into the spinal cord to aspirate any cysts which might have .been present, but no fluid emerged. In suturing the wound, Dr. Spence attempted to relieve the pressure on the spinal cord by enlarging the dura —the outer protective wall of the spinal eord^-at the area of swelling.

For approximately the first day after the operation appellant recuperated normally, but then suffered a fall and an almost immediate setback. Since there is some conflict as to precisely when or why appellant fell, 4 we reconstruct the events from the evidence most favorable to him. 5 Dr. Spence left orders that appellant was to remain in bed during the process of voiding. These orders were changed to direct that voiding be done out of bed, and the jury could find that the change was made by hospital personnel. Just prior to the fall, appellant summoned a nurse and was given a receptacle for use in voiding, but was then left unattended. Appellant testified that during the course of the endeavor he slipped off the side of the bed, and that there was no one to assist him, or side rail to prevent the fall.

Several hours later, appellant began to complain that he could not move his legs and that he was having trouble breathing; paralysis seems to have been virtually total from the waist down. Dr. Spence was notified on the night of February 12, and he rushed to the hospital. Mrs. Canterbury signed another consent form and appellant was again taken into the operating room. The surgical wound was reopened and Dr. Spense created a gusset to allow the spinal cord greater room in which to pulsate.

Appellant’s control over his muscles improved somewhat after the second operation but he was unable to void properly. As a result of this condition, he came under the care of a urologist while *778 still in the hospital. In April, following a cystoscopic examination, appellant was operated on for removal of bladder stones, and in May was released from the hospital. He reentered the hospital the following August for a 10-day period, apparently because of his urologic problems. For several years after his discharge he was under the care of several specialists, and at all times was under the care of a urologist. At the time of the trial in April, 1968, appellant required crutches to walk, still suffered from urinal incontinence and paralysis of the bowels, and wore a penile clamp.

In November, 1959 on Dr. Spence’s recommendation, appellant was transferred by the F.B.I. to Miami where he could get more swimming and exercise. Appellant worked three years for the F.B.I. in Miami, Los Angeles and Houston, resigning finally in June, 1962. From then until the time of the trial, he held a number of jobs, but had constant trouble finding work because he needed to remain seated and close to a bathroom. The damages appellant claims include extensive pain and suffering, medical expenses, and loss of earnings.

II

Appellant filed suit in the District Court on March 7, 1963, four years after the laminectomy and approximately two years after he attained his majority. The complaint stated several causes of action against each defendant. Against Dr. Spence it alleged, among other things, negligence in the performance of the laminectomy and failure to inform him beforehand of the ..risk involved. Against the hospital the complaint charged negligent post-operative care in permitting appellant to remain unattended after the laminectomy, in failing to provide a nurse or orderly to assist him at the time of his fall, and in failing to maintain a side rail on his bed. The answers denied the allegations of negligence and defended on the ground that the suit was barred by the statute of lim-** itations.

Pretrial discovery — including depositions by appellant, his mother and Dr. Spence — continuances and other delays consumed five years. At trial, disposition of the threshold question whether the statute of limitations had run was held in abeyance until the relevant facts developed. Appellant introduced no evidence to show medical and hospital practices, if any, customarily pursued in regard to the critical aspects of the case, and only Dr. Spence, called as an adverse witness, testified on the issue of causality. Dr. Spence described the surgical procedures he utilized in the two operations and expressed his opinion that appellant’s disabilities stemmed from his pre-operative condition as symptomized by the swollen, non-pulsating spinal cord. He stated, however, that neither he nor any of the other physicians with whom he consulted was certain as to what that condition was, and he admitted that trauma can be a cause of paralysis. Dr. Spence further testified that even without trauma paralysis can be anticipated “somewhere in the nature of one percent” of the laminectomies performed, a risk he termed “a very slight possibility.” He .feltthat .communication of that..risk-to the patient is not good medical practice because it might deter 'patients. from undergoing needed surgery and might produce' adverse psychological reactions which eoúld preclude the success of the operation.

At the close of appellant’s case in chief, each defendant moved for a directed verdict and the trial judge granted both motions. The basis of the ruling, he explained, was that appellant had failed to produce any medical evidence indicating negligence on Dr. Spence’s part in diagnosing appellant’s malady or in performing the laminectomy; that there was no proof that Dr. Spence’s treatment was responsible for appellant’s disabilities; and that notwithstanding some evidence to show negligent post-operative care, an absence of medical testimony to show causality precluded submission of the case against the hospital to the jury. *779 The judge did not allude specifically to the alleged breach of duty by Dr. Spence to divulge the possible consequences of the laminectomy.

We reverse. The testimony of appellant and his mother that Dr. Spence did not reveal the risk of paralysis from the laminectomy made out a prima facie case of violation of the physician’s duty to disclose which Dr. Spence’s explanation-did not negate as a matter of law. There was also testimony from which the jury could have found that the laminectomy was negligently performed by Dr. Spence, and that appellant’s fall was the consequence of negligence on the part of the hospital. The record, moreover, contains evidence of sufficient quantity and quality to tender jury issues as to whether and to what extent any such negligence was causally related to appellant’s post-laminectomy condition. These considerations entitled appellant to a new trial.

Elucidation of our reasoning necessitates elaboration on a number of points. In Parts III and IV we explore the origins and rationale of the physician’s duty to reasonably inform an ailing patient as to the treatment alternatives available and the risks incidental to them. In Part V we investigate the scope of the disclosure requirement and in Part VI the physician’s privileges not to disclose. In Part VII we examine the role of causality, and in Part VIII the need for expert testimony in non-disclosure litigation. In Part IX we deal with appellees’ statute of limitations defense and in Part X we apply the principles discussed to the case at bar.

Ill

Suits charging failure by a physician 6 adequately to disclose the risks and alternatives of proposed treatment are not innovations In American law. They date back a good half-century, 7 and in the last decade they have multiplied rapidly. 8 There is, nonetheless, disagreement among the courts and the commentators 9 on many major questions, and there is no precedent of our own directly in point. 10 For the tools enabling resolu *780 tion of the issues on this appeal, we are forced to begin at first principles. 11

The root premise is the concept, fundamental in American jurisprudence, that “[e]very human being of adult years and sound mind has a right to determine what shall be done with his own body. . . . ” 12 True consent to what happens to one’s self is the informed exercise of a choice, and that entails an opportunity to evaluate knowledgeably the options available and the risks attendant upon each. 13 The average patient has little or no understanding of the medical arts, and ordinarily has only his physician to whom he can look for enlightenment with which to reach an intelligent decision. 14 From these almost axiomatic considerations springs the need, and in turn the requirement, of a reasonable divulgenee by physician to patient to make such a decision possible. 15

*781 A physician is under a duty to treat his patient skillfully 16 but proficiency in diagnosis and therapy is not the full measure of his responsibility. The cases demonstrate that the physician is under an obligation to communicate specific information to the patient when the exigencies of reasonable care call for it. 17 Due care may require a physician perceiving symptoms of bodily abnormality to alert the patient to the condition. 18 It may call upon the physician confronting an ailment which does not respond to his ministrations to inform the patient thereof. 19 It may command the physician to instruct the patient as to any limitations to be presently observed for his own welfare, 20 and as to any precautionary therapy he should seek in the future. 21 It may oblige the physician to advise the patient of the need for or desirability of any alternative treatment promising greater benefit than that being pursued. 22 Just as plainly, due care normally demands that the physician warn the patient of any risks to his well-being which contemplated therapy may involve. 23

The context in which the duty of risk-disclosure arises is invariably the occasion for decision as to whether a particular treatment procedure is to be undertaken. To the physician, whose training enables a self-satisfying evaluation, the answer may seem clear, but it is the prerogative of the patient, not the physician, to determine for himself the direction in which his interests seem to lie. 24 To enable the patient to chart his course understandably, some familiarity with the therapeutic alternatives and their hazards becomes essential. 25

*782 A reasonable revelation in these respects is not only a necessity but, as we see it, is as much a matter of the physician’s duty. Ijt is a duty to warn of the dangers lurking in the proposed treatment, and that is surely a facet of due care. 26 It is, too, a duty to impart information which the patient has every right to expect. 27 The patient’s reliance upon the physician is a trust of the kind which traditionally has exacted obligations beyond those associated with arms-length transactions. 28 His dependence upon the physician for information affecting his well-being,' in terms of contemplated treatment, is well-nigh abject. As earlier noted, long before the instant litigation arose, courts had recognized that the physician had the responsibility of satisfying the vital informational needs of the patient. 29 | More recently, we ourselves have found “in the fiducial qualities of [the physician-patient] relationship the physician’s duty to reveal to the patient that which in his best interests it is important that he should know.” 30 We now find, as a part of the physician’s overall obligation to the patient, a similar duty of reasonable disclosure of the choices with respect to proposed therapy and the dangers inherently and potentially involved. 31

This disclosure requirement, on analysis, reflects much more of a change in doctrinal emphasis than a substantive addition to malpractice law. It is well established that the physician must seek and secure his patient’s consent before commencing an operation or other course of treatment. 32 It is also *783 clear that the consent, to be efficacious, must be free from imposition upon the patient. 33 It is the settled rule that therapy not authorized by the patient may amount to a tort — a common law battery —by the physician. 34 And it is evident that it is normally impossible to obtain a consent worthy of the name unless the physician first elucidates the options and the perils for the patient’s edification. 35 Thus the physician has long borne a duty, on pain of liability for unauthorized treatment, to make adequate disclosure to the patient. 36 The evolution of the obligation to communicate for the patient’s benefit as well as the physician’s protection has hardly involved an extraordinary restructuring of the law.

IV

Duty to disclose has gained recognition in a large number of American jurisdietions, 37 but more largely on a different rationale. The majority of courts dealing with the problem have made the duty depend on whether it was the custom of physicians practicing in the community to make the particular disclosure to the patient. 38 If so, the physician may be held liable for an unreasonable and injurious failure to divulge, but there can be no recovery unless the omission forsakes a practice prevalent in the profession. 39 We agree that the physician’s noncompliance with a professional custom to reveal, like any other departure from prevailing medical practice, 40 may give rise to liability to the patient. We do not agree that the patient’s cause of action is dependent upon the existence and nonperformance of a relevant professional tradition.

There are, in our view, formidable obstacles to acceptance of the notion that the physician’s obligation to disclose is either germinated or limited by medical practice. To begin with, the reality of any discernible custom reflecting a professional concensus on communication of option and risk information to patients is open to serious doubt. 41 We sense the danger that what in fact is no *784 custom at all may be taken as an affirmative custom to maintain silence, and that physician-witnesses to the so-called custom may state merely their personal opinions as to what they or others would do under given conditions. 42 We cannot gloss over the inconsistency between reliance on a general practice respecting divulgence and, on the other hand, realization that the myriad of variables among patients 43 makes each case so different that its omission can rationally be justified only by the effect of its individual circumstances. 44 Nor can we ignore the fact that to bind the disclosure obligation to medical usage is to arrogate the decision on revelation to the physician alone. 45 Respect for the patient’s right of self-determination on particular therapy 46 demands a standard set by law for physicians rather than one which physicians may or may not impose .upon themselves. 47

More fundamentally, the majority rule overlooks the graduation of reasonable-care demands in Anglo-American jurisprudence and the position of professional custom in the hierarchy. The caliber of the performance exacted by the reasonable-care standard varies between the professional and non-professional worlds, and so also the role of professional custom. “With but few exceptions,” we recently declared, “society demands that everyone under a duty to use care observe minimally a general standard.” 48 “Familiarly expressed judicially,” we added, “the yardstick is that degree of care which a reasonably prudent person would have exercised under the same or similar circumstances." 49 “Beyond this,” however, we emphasized, “the law requires those engaging in activities requiring unique knowledge and ability to give a performance commensurate with the undertaking.” 50 Thus physicians treating the sick must perform at higher levels than non-physicians in order to meet the reasonable care standard in its special application to physicians 51 — “that degree of care and skill ordinarily exercised by the profession in [the physician’s] own or similar localities.” 52 And practices adopted by the profession have indispensable value as evidence tending to establish just what that degree of care and skill is. 53

We have admonished, however, that “[t]he special medical standards 54 are but. adaptions of the general standard to a group who are required to act as *785 reasonable men possessing their medical talents presumably would.” 55 There is, by the same token, no basis for operation of the special medical standard where the physician’s activity does not bring his .medical knowledge and skills peculiarly .into play. 56 And where the challenge to the physician’s conduct is not to be gauged by the special standard, it follows that medical custom cannot furnish the test of its propriety, whatever its relevance under the proper test may be. 57 The decision to unveil the patient’s condition and the chances as to remediation, as we shall see.Js ofttimes a non-medical judgment 58 and, if so, is a decision out.side the ambit of the special standard. Where that is the situation, professional custom hardly furnishes the legal criterion for measuring the physician’s responsibility to reasonably inform his patient of the options and the hazards as to treatment.

The majority rule, moreover, is at war with our prior holdings that a showing of medical practice, however probative, does not fix the standard governing recovery for medical malpractice. 59 .Prevailing medical practice, we have maintained, has_evidentiary value in determinations as to what the specific criteria measuring challenged professional conduct are and whether they have been met, 60 but does not itself define the standard. 61 That has been our position in treatment cases, where the physician’s performance is ordinarily to be adjudicated by the special medical standard of due care. 62 We see no logic in a different rule for nondisclosure cases, where the governing standard is much more largely divorced from professional considerations. 63 And surely in nondisclosure cases the factfinder is not invariably functioning in an area of such technical complexity that it must be bound to medical custom as an inexorable application of the community standard of reasonable care. 64

Thus we distinguished, for purposes of duty to disclose, the speeial- and general-standard aspects of the physician-patient relationship. When medical judgment enters the picture and for 'that reason the special standard controls, prevailing medical practice must be given its just due. In all other instances, however, the general standard exacting ordinary care applies, and that standard is set by law. In sum, the physician’s duty to disclose is governed by the same legal principles applicable to others in comparable situations, with modifications only to the extent that medical judgment enters the picture. 65 We hold that the standard measuring, performance of that duty by physicians, as by others, is conduct which is reasonable under the circumstances. 66

*786 V

Once the circumstances give rise to a duty on the physician’s part to inform his patient, the next inquiry is the_scope of the disclosure the physician is legally obliged to make. The courts have frequently confronted this problem but no uniform standard defining the adequacy of the divulgenee emerges from the decisions. Some have said “full” disclosure, 67 a norm we are unwilling to adopt literally. It seems obviously prohibitive and unrealistic to expect physicians to discuss with their patients every risk of proposed treatment — no matter how small or remote 68 — and generally unnecessary from the patient’s viewpoint as well. Indeed, the cases speaking in terms of “full” disclosure appear to envision something less than total disclosure, 69 leaving unanswered the question of just how much.

The larger number of courts, as might be expected, have applied tests framed with reference to prevailing fashion within the medical profession. 70 Some have measured the disclosure by “good medical practice,” 71 others by what a reasonable practitioner would have bared under the circumstances, 72 and still others by what medical custom in the community would demand. 73 JVe have explored this rather considerable body of law but are unprepared to follow it. The duty to disclose, we have reasoned, arises from phenomena apart from medical custom and practice. 74 The latter, we think, should no more establish the scope of the duty than its existence. Any definition of scope in terms purely of a professional standard is at odds with the patient’s prerogative to decide on projected therapy himself. 75 That prerogative, we have said, is at the very foundation of the duty to disclose, 76 and both the patient’s right to know and the physician’s correlative obligation to tell him are diluted to the extent that its compass is dictated by the medical profession. 77

In our view, the patient’s right of self-decision shapes the boundaries of the duty to reveal. That right can be effectively exercised only if the patient possesses enough information to enable an intelligent choice.’ The scope of the physician’s communications to the patient, then, must bef measured by the patient’s need, 78 and that need is the information material to the decision. Thus tlie test for determining whether a par *787 ticular peril must be divulged is its materiality to the patient’s decision: all risks, potentially affecting the decision must be unmasked. 79 And to safeguard the patient’s interest in achieving his own determination on treatment, the law must itself set the standard for adequate disclosure. 80

Optimally for the patient, exposure of a risk would be mandatory whenever the patient would deem it significant to his decision, either singly or in combination with other risks. Such a requirement, however, would summon the physician to second-guess the patient, whose ideas on materiality could hardly be known to the physician. That would make an undue demand upon medical practitioners, whose conduct, like that of others, is to be- measured in terms of reasonableness. Consonantly with orthodox negligence doctrine, the physician’s liability for nondisclosure is to be determined on the basis of foresight, not hindsight; no less than any other aspect of negligence, the issue on nondisclosure must be approached from the viewpoint of the reasonableness of the physician’s divulgence jn terms of what he knows or should know to be the patient’s informational needs. If, but only if, the fact-finder can say that the physician’s communication was unreasonably inadequate is an imposition of liability legally or morally justified. 81

Of necessity, the content of the disclosure rests in the first instance with the physician. Ordinarily it is only he who is in position to identify particular dangers; always he must make a judgment, in terms of materiality, as to whether and to what extent revelation to the patient is called for. He cannot know with complete exactitude what the patient would consider important to his decision, but on the basis of his medical training and experience he can sense how the average, reasonable patient expectably would react. 82 Indeed, with knowledge of, or ability to learn, his patient’s background and current condition, he is in a position superior to that of most others — attorneys, for example — who are called upon to make judgments on pain of liability in damages for unreasonable miscalculation. 83

From these considerations we derive the breadth of the disclosure of risks legally to be required. The scope of the standard is not subjective as to either the physician or the patient; it remains objective with due regard for the patient’s informational needs and with suitable leeway for the physician’s situation. In broad outline, we agree that,“[a] risk is thus material when a reasonable person, in what the physician knows or should know to be the patient’s position, would be likely to attach significance to the risk or.cluster of risks in deciding whether or not to forego the proposed therapy.” 84

The topics importantly demanding a communication of information are the inherent and potential hazards of the proposed treatment, the alternatives to *788 that treatment, if any, and the results likely if the patient remains untreated. The factors contributing significance to the dangerousness of a medical technique are, of course, the incidence of injury and the degree of the harm threatened. 85 A very small chance of death or serious disablement may well be significant; a potential disability which dramatically outweighs the potential benefit of the therapy or the detriments of the existing malady may summons discussion with the patient 86

There is no bright line separating the significant from the insignificant ; the answer in any case must abide a rule of reason. Some dangers — infection, for example — are inherent in any operation; there is no obligation to communicate those of which persons of average sophistication are aware. 87 Even more clearly, the physician bears no responsibility for discussion of hazards the patient has already discovered, 88 or those having no apparent materiality to patients’ decision on therapy. 89 The disclosure doctrine, like others marking lines between permissible and impermissible behavior in medical practice, is in essence a requirement of conduct prudent under the circumstances. Whenever nondisclosure of particular risk information is open to debate by reasonable-minded men, the issue is for the finder of the facts. 90

VI

Two exceptions to the general rule of disclosure have been noted by the courts. Each is in the nature of a physician’s privilege not to disclose, and the reasoning underlying them is appealing. Each, indeed, is but a recognition that, as important as is the patient’s right to know, it is greatly outweighed by the magnitudinous circumstances giving rise to the privilege. The first comes into play when the patient is unconscious or otherwise incapable of consenting, and harm from a failure to treat is imminent and outweighs any harm threatened by the proposed treatment. When a genuine emergency of that sort arises, it is settled that the impracticality of confer *789 ring with the patient dispenses with need for it. 91 Even in situations of that character the physician should, as current law requires, attempt to secure a relative’s consent if possible 92 But if time is too short to accommodate discussion, obviously the physician should proceed with the treatment. 93

The second exception obtains when risk-disclosure poses such a threat of detriment to the patient as to become unfeasible or contraindicated from a medical point of view. It is recognized that patients occasionally become so ill or emotionally distraught on disclosure as to foreclose a rational decision, or complicate or hinder the treatment, or perhaps even pose psychological damage to the patient. 94 Where that is so, the cases have generally held that the physician is armed with a privilege to keep the information from the patient, 95 and we think it clear that portents of that type may justify the physician in action he deems medically warranted. The critical inquiry is whether the physician responded to a sound medical judgment that communication of the risk information would present a threat to the patient’s well-being.

The physician’s privilege to withhold information for therapeutic reasons must be carefully circumscribed, however, for otherwise it might devour the disclosure rule itself. The privilege does not accept the paternalistic notion that the physician may remain silent simply because divulgence might prompt the patient to forego therapy the physician feels the patient really needs. 96 That attitude presumes instability or perversity for even the normal patient, and runs counter to the foundation principle that the patient should and ordinarily can make the choice for himself. 97 Nor does the privilege contemplate operation save where the patient’s reaction to risk information, as reasonable foreseen by the physician, is menacing. 98 And even in a situation of that kind, disclosure to a close relative with a view to securing consent to the proposed treatment may be the only alternative open to the physician. 99

*790 VII

No more than breach of any other legal duty does nonfulfillment of the physician’s obligation to disclose alone establish liability to the patient. An unrevealed risk that should have been made known must materialize, for otherwise the omission, however unpardonable, is legally without consequence. Occurrence of the risk must be harmful to the patient, for negligence unrelated to injury is nonaetionable. 100 And, as in malpractice actions generally, 101 there must be a causal relationship between the physician’s failure to adequately divulge and damage to the patient. 102

A causal connection exists when, but only when, disclosure of significant risks incidental to treatment would have resulted in a decision against it. 103 The patient obviously has no complaint if he would have submitted to the therapy notwithstanding awareness that the risk was one of its perils. On the other hand, the very purpose of the disclosure rule is to protect the patient against consequences which, if known, he would have avoided by foregoing the treatment. 104 The more difficult question is whether the factual issue on causality calls for an objective or a subjective determination.

It has been assumed that the issue is to be resolved according to whether the factfinder believes the patient’s testimony that he would not have agreed to the treatment if he had known of the danger which later ripened into injury. 105 We think a technique which ties the factual conclusion on causation simply to the assessment of the patient’s credibility is unsatisfactory. To be sure, the objective of risk-disclosure is preservation of the patient’s interest in intelligent self-choice on proposed treatment, a matter the patient is free to decide for any reason that appeals to him. 106 When, prior to commencement of therapy, the patient is sufficiently informed on risks and he exercises his choice, it may truly be said that he did exactly what he wanted to do. But when causality is explored at a post-injury trial with a professedly uninformed patient, the question whether he actually would have turned the treatment down if he had known the risks is purely hypothetical: “Viewed from the point at which he had to decide, would the patient have decided differently had he known something he did not know?” 107 And the answer which the patient supplies hardly represents more than a guess, perhaps tinged by the circumstance that the uncommunicated hazard has in fact materialized. 108

In our view, this method of dealing with the issue on causation comes in second-best. It places the physician in jeop *791 ardy of the patient’s hindsight and bitterness. It places the factfinder in the position of deciding whether a speculative answer to a hypothetical question is to be credited. It calls for a subjective determination solely on testimony of a patient-witness shadowed by the occurrence of the undisclosed risk. 109

Better it is, we believe, to resolve the causality issue on an objective basis: in terms of what a prudent person in the patient’s position would have decided if suitably informed of all perils bearing significance. 110 If adequate disclosw. could reasonably be expected to llave caused that person to decline the treatment because of the revelation of the kind of risk or danger that resulted in harm, causation is shown, but otherwise not. 111 The patient’s testimony is relevant on that score of course but it would not threaten to dominate the findings. And since that testimony would probably be appraised congruently with the factfinder’s belief in its reasonableness, the case for a wholly objective standard for passing on causation is strengthened. Such a standard would in any event ease the fact-finding process and better assure the truth as its product.

VIII

In the context of trial of a suit claiming inadequate disclosure of risk information by a physician, the patient has the burden of going forward with evidence tending to establish prima facie the essential elements of the cause of action, and ultimately the burden of proof — the risk of nonpersuasion 112 — on those elements. 113 These are normal impositions upon moving litigants, and no reason why they should not attach in nondisclosure cases is apparent. The burden of going forward with evidence pertaining to a privilege not to disclose, 114 however, rests properly upon the physician. This is not only because the patient has made out a prima facie case before an issue on privilege is reached, but also because any evidence bearing on the privilege is usually in the hands of the physician alone. Requiring him to open the proof on privilege is consistent with judicial policy laying such a burden on the party who seeks shelter from an exception to a general rule and who is more likely to have possession of the facts. 115

As in much malpractice litigation, 116 recovery in nondisclosure lawsuits has hinged upon the patient’s ability to prove through expert testimony that the physician’s performance departed from medical custom. This is not surprising since, as we have pointed out, the majority of American jurisdictions have limited the patient’s right to know to whatever boon can be found in medical practice. 117 We have already discussed our disagreement with the majority rationale. 118 We now delineate our view on the need for expert testimony in nondisclosure cases.

There are obviously important roles for medical testimony in such cases, and some roles which only medical evidence can fill: Experts are ordinarily indispensible to identify and elucidate for the factfinder the risks of therapy and *792 the consequences of leaving existing maladies untreated. They are normally needed on issues as to the cause of any injury or disability suffered by the patient and, where privileges are asserted, as to the existence of any emergency claimed and the nature and seriousness of any impact upon the patient from risk-disclosure. Save for relative infrequent instances where questions of this type are resolvable wholly within the realm of ordinary human knowledge and experience, the need for the expert is clear. 119

The guiding consideration our decisions distill, however, is that medical facts are for medical experts 120 and other facts are for any witnesses- — expert or not — having sufficient knowledge and capacity to testify to them. 121 It is evident that many of the issues typically involved in nondisclosure cases do not reside peculiarly within the medical domain. Lay witness testimony can competently establish a physician’s failure to disclose particular risk information, the patient’s lack of knowledge of the risk, and the adverse consequences following the treatment. 122 Experts are unnecessary to a showing of the materiality of a risk to a patient’s decision on treatment, or to the reasonably, expectable effect of risk disclosure on the decision. 123 These conspicuous examples of permissible uses of nonexpert testimony illustiv. the relative freedom of broad areas of the legij problem of risk nondisclosure from the demands for expert testimony that shackle plaintiffs’ other types of medical malpractice litigation. 124

*793 IX

We now confront the question whether appellant’s suit was barred, wholly or partly, by the statute of limitations. The statutory periods relevant to this inquiry are one year for battery actions 125 and three years for those charging negligence. 126 For one a minor when his cause of action accrues, they do not begin to run until he has attained his majority. 127 Appellant was nineteen years old when the laminectomy and related events occurred, and he filed his complaint roughly two years after he reached twenty-one. Consequently, any claim in suit subject to the one-year limitation came too late.

Appellant’s causes of action for the allegedly faulty laminectomy by Dr. Spence and allegedly careless post-operative care by the hospital present no problem. Quite obviously, each was grounded in negligence and so was governed by the three-year provision. 128 The duty-to-disclose claim appellant asserted against Dr. Spence, however, draws another consideration into the picture. We have previously observed that an unauthorized operation constitutes a battery, and that an uninformed consent to an operation does not confer the necessary authority. 129 If, therefore, appellant had at stake no more than a recovery of damages on account of a laminectomy intentionally done without intelligent permission, the statute would have interposed a bar.

It is evident, however, that appellant had much more at stake. 130 His interest in bodily integrity commanded protection, not only against an intentional invasion by an unauthorized operation 131 but also against a negligent invasion by his physician’s dereliction of duty to adequately disclose. 132 Appellant has asserted and litigated a violation of that duty throughout the case. 133 That claim, like the others, was governed by the three-year period of limitation applicable to negligence actions 134 and was *794 unaffected by the fact that its alternative was barred by the one-year period pertaining to batteries. 135

X

This brings us to the remaining question, common to all three causes of action: whether appellant’s evidence was of such caliber as to require a submission to the jury. On the first, the evidence was clearly sufficient to raise an issue as to whether Dr. Spence’s obligation to disclose information on risks was reassonably met or was excused by the surrounding circumstances. Appellant testified that Dr. Spence revealed to him nothing suggesting a hazard associated with the laminectomy. His mother testified that, in response to her specific inquiry, Dr. Spence informed her that the laminectomy was no more serious than any other operation. When, at trial, it developed from Dr. Spence’s testimony that paralysis can be expected in one percent of laminectomies, it became the jury’s responsibility to decide whether that peril was of sufficient magnitude to bring the disclosure duty into play. 136 There was no emergency to frustrate an opportunity to disclose, 137 and Dr. Spence’s expressed opinion that disclosure would have been unwise did not foreclose a contrary conclusion by the jury. There was no evidence that appellant’s emotional makeup was such that concealment of the risk of paralysis was medically sound. 138 Even if disclosure to appellant himself might have bred ill consequences, no reason appears for the omission to communicate the information to his mother, particularly in view of his minority. 139 The jury, not Dr. Spence, was the final arbiter of whether nondisclosure was reasonable under the circumstances. 140

Proceeding to the next cause of action, we find evidence generating issues as to whether Dr. Spence performed the laminectomy negligently and, if so, whether that negligence contributed causally to appellant’s subsequent disabilities. A report Dr. Spence prepared after the second operation indicated that at the time he felt that too-tight sutures at the laminectomy site might have caused the paralysis. While at trial Dr. Spence voiced the opinion that the sutures were not responsible, there were circumstances lending support to his original view. Prior to the laminectory, appellant had *795 none of the disabilities of which he now complains. The disabilities appeared almost immediately after the laminectomy. The gusset Dr. Spence made on the second operation left greater room for the spinal cord to pulsate, and this alleviated appellant’s condition somewhat. That Dr. Spence’s in-trial opinion was hardly the last word is manifest from the fact that the team of specialists consulting on appellant was unable to settle on the origin of the paralysis.

We are advertent to Dr. Spence’s attribution of appellant’s disabilities to his condition preexisting the laminectomy, but that was a matter for the jury. And even if the jury had found that theory acceptable, there would have remained the question whether Dr. Spence aggravated the preexisting condition. A tortfeasor takes his victim as he finds him, and negligence intensifying an old condition creates liability just as surely as negligence precipitating a new one. 141 It was for the jury to say, on the whole evidence, just what contributions appellant’s preexisting condition and Dr. Spence’s medical treatment respectively made to the disabilities.

In sum, judged by legal standards, the proof militated against a directed verdict in Dr. Spence’s favor. True it is that the evidence did not furnish ready answers on the dispositive factual issues, but the important consideration is that appellant showed enough to call for resolution of those issues by the jury. As in Sentilles v. Inter-Carribbean Shipping Corporation, 142 a case resembling this one, the Supreme Court stated,

The jury’s power to draw the inference that the aggravation of petitioner’s tubercular condition, evident so shortly after the accident, was in fact caused by that accident, was not impaired by the failure of any medical witness to testify that it was in fact the cause. Neither can it be impaired by the lack of medical unanimity as to the respective likelihood of the potential causes of the aggravation, or by the fact that other potential causes of aggravation existed and were not conclusively negated by the proofs. The matter does not turn on the use of a particular form of words by the physicians in giving their testimony. The members of the jury, not the medical witnesses, were sworn to make a legal determination of the question of causation. They were entitled to take all the circumstances, including the medical testimony into consideration. 143

We conclude, lastly, that the case against the hospital should also have gone to the jury. The circumstances surrounding appellant’s fall — the change in Dr. Spence’s order that appellant be kept in bed, 144 the failure to maintain a side rail on appellant’s bed, and the absence of any attendant while appellant was attempting to relieve himself — could certainly suggest to jurors a dereliction of the hospital’s duty to exercise reasonable care for the safety and well-being of the patient. 145 On the issue of causality, the *796 evidence was uneontradicted that appellant progressed after the operation until the fall but, a few hours thereafter, his condition had deteriorated, and there were complaints of paralysis and respiratory difficulty. That falls tend to cause or aggravate injuries is, of course, common knowledge, which in our view the jury was at liberty to utilize. 146 To this may be added Dr. Spence’s testimony that paralysis can be brought on by trauma or shock. All told, the jury had available a store of information enabling an intelligent resolution of the issues respecting the hospital. 147

We realize that, when appellant rested his case in chief, the evidence scarcely served to put the blame for appellant’s disabilities squarely on one appellee or the other. But this does not mean that either could escape liability at the hand of the jury simply because appellant was unable to do more. As ever so recently we ruled, “a showing of negligence by each of two (or more) defendants with uncertainty as to which caused the harm does not defeat recovery but passes the burden to the tortfeasors for each to prove, if he can, that he did not cause the harm.” 148 In the case before us, appellant’s evidentiary presentation on negligence survived the claims of legal insufficiency, and appellees should have been put to their proof. 149

Reversed and remanded for a new trial.

*120 OPINION

HOLDER, J.

We granted this appeal to address the appropriate standard to be employed when assessing the issue of causation in a medical malpractice informed consent case. We find that the objective standard as set forth in this opinion best balances a patient’s right to self-determination with the need for a realistic framework for rational resolution of the issue of causation. We hold that the standard to be applied in informed consent cases is whether a reasonable person in the patient’s position would have consented to the procedure or treatment in question if adequately informed of all significant perils. The decision of the Court of Appeals is affirmed, and the case is remanded to the trial court for a new trial.

BACKGROUND

The plaintiff, Patricia P. Ashe, was diagnosed with breast cancer in 1988. She ultimately underwent a double mastectomy and chemotherapy as treatment for her breast cancer. In 1993, she began experiencing problems with a cough and a fever. She returned to her oncologist, Dr. Michael Kuzu, where she presented symptoms of fever, cough, pain in the abdomen, weight loss, decreased appetite, and irritability. A chest x-ray and a CT scan revealed the presence of a mass in the medial left apex of her left lung.

The record indicates that the lung tumor could possibly have been metastatic cancer from the breast. Ms. Ashe underwent surgery, and the upper portion of her left lung was removed. She underwent chemotherapy and was referred to the defendant, Dr. Steven L. Stroup, for consideration of radiation therapy. Dr. Stroup testified that chemotherapy alone would be indicated if the lung tumor were metastasized breast cancer. He, however, opined that radiation therapy would be indicated if the lung cancer were primary as opposed to secondary cancer.

Dr. Stroup prescribed radiation treatment for Ms. Ashe. She received a daily dose of 200 centigray for twenty-five days. He described the dose as a “midplane dose.” Ms. Ashe sustained “radiation myelitis” caused by a permanent radiation injury to her spinal cord. She is now a paraplegic.

Dr. Stroup did not inform Ms. Ashe that the radiation treatment might result in a permanent injury to her spinal cord. According to Dr. Stroup, the risk that she would sustain a spinal cord injury was less than one percent. Mrs. Ashe proffered the testimony of her expert, Dr. Carlos Perez. Dr. Perez opined that the risk of spinal cord injury was one to two percent. Dr. Perez testified that the applicable standard of care required physicians to warn patients about the risk of radiation injury to the spinal cord.

Ms. Ashe filed the present action alleging claims for medical malpractice and lack óf informed consent. At trial, she testified that she would not have consented to the radiation therapy had she been informed of the risk of paralysis. Defense counsel on cross-examination pointed out that the plaintiff did equivocate in her deposition on the issue o'f consent. Her deposition testimony indicated that she did not know what she would have done had she been warned about the risk of spinal cord injury. She then testified on redirect examination as follows:

True, but the risk of being paralyzed and put in a wheelchair for the rest of your life was not one of the items, if there was any discussed, because had he said that within a six-month period-which they said that would be the time frame for it to happen-had he said, ‘Patty, if you do this there is a risk that you will be in a wheelchair six months from now,’ I would have told him, T will take my chances.’ I would not have it done.

The trial court found that the plaintiffs trial testimony conflicted with her deposition testimony regarding whether she *121 would have consented to the procedure had she been warned of the risk of spinal cord injury. The trial court, therefore, struck the trial testimony and granted the defendant a directed verdict on the informed consent claim. The plaintiffs malpractice claim went to the jury. The jury was unable to reach a verdict, and a mistrial was declared.

The plaintiff appealed to the Court of Appeals. The Court of Appeals held that as part of the plaintiffs informed consent claim she was required to prove that a reasonable person knowing of the risk for spinal cord injury would have decided not to have had the procedure performed. The Court held that the discrepancy between the trial testimony and deposition testimony went to the issue of credibility and that the trial testimony should not have been stricken. The Court of Appeals reversed the trial court’s grant of a directed verdict on the informed consent claim and remanded the case for a new trial.

ANALYSIS

The burden of proof on the standard of care element in medical malpractice informed consent cases is controlled by Tenn.Code Ann. § 29-26-118. Pursuant to § 29-26-118, a plaintiff must prove by expert testimony that

the defendant did not supply appropriate information to the patient in obtaining his informed consent to the procedure out of which plaintiffs claim allegedly arose in accordance with the recognized standard of acceptable professional practice in the profession and in the specialty, if any, that the defendant practices in the community in which he practices or in similar communities.

Id. In addition, TenmCode Ann. § 29-26-115 requires that the plaintiff prove the recognized standard of acceptable professional practice, that the defendant acted with less than ordinary and reasonable care in accordance with that standard, and that the plaintiff sustained injuries as a result of the defendant’s negligent act or omission. Accordingly, the plaintiff in an informed consent medical malpractice case has the burden of proving: (1) what a reasonable medical practitioner in the same or similar community would have disclosed to the patient about the risk posed by the proposed procedure or treatment; and (2) that the defendant departed from the norm. German v. Nichopoulos, 577 S.W.2d 197, 204 (Tenn. Ct. App.1978).

This Court recently enunciated a distinction between a lack of informed consent case and a pure medical battery case. In Blanchard v. Kellum, 975 S.W.2d 522 (Tenn.1998), this Court defined a medical battery as a case in which a doctor performs an unauthorized procedure. Id. at 524. A medical battery may typically occur when: (1) a professional performs a procedure that the patient was unaware the doctor was going to perform; or (2) the procedure was performed on a part of the body other than that part explained to the patient (i.e., amputation of the wrong leg). Id. A lack of informed consent claim typically occurs when the patient was aware that the procedure was going to be performed but the patient was unaware of the risk associated with the procedure. Id.

The case now before us is not a medical battery case. Ms. Ashe had authorized the radiation treatment. Ms. Ashe, however, contends that she was not apprised of certain risks inherent in the treatment. Her claim, therefore, is premised on the lack of informed consent.

The issue with which we are now confronted is whether an objective, subjective, or a hybrid subjective/objective test shall be employed when assessing causation in medical malpractice informed consent cases. The issue is one of first impression in Tennessee. The majority of jurisdictions having addressed this issue follow an objective standard. A minority of jurisdictions having addressed the issue follow the subjective approach. One jurisdiction, Hawaii, employed a “modified objective stan *122 dard” for informed consent cases for approximately ten years. Hawaii has now abandoned the modified approach in favor of the objective standard. We shall now examine the various approaches and the rationales behind these approaches.

Subjective Standard

The plaintiff urges this Court to follow the minority rule or adopt a subjective standard when evaluating causation in an informed consent case. Causation under the subjective standard is established solely by patient testimony. Patients must testify and prove that they would not have consented to the procedures had they been advised of the particular risk in question. See e.g., Scott v. Bradford, 606 P.2d 554 (Okla.1979); Wilkinson v. Vesey, 110 R.I. 606, 295 A.2d 676 (1972). Accordingly, resolution of causation under a subjective standard is premised elusively on the credibility of a patient’s testimony.

The subjective standard engages in an abstract analysis. The abstract analysis not only poses a purely hypothetical question but seeks to answer the hypothetical question. One commentator has framed this hypothetical question as follows: “Viewed from the point at which [the patient] had to decide, would the patient have decided differently had he known something he did not know?” Canterbury v. Spence, 464 F.2d 772, 790 (D.C.Cir.1972) quoting Waltz & Scheuneman, Informed Consent to Therapy, 64 Nw.U.L.Rev. 628, 647 (1970).

Proponents of the subjective test argue that a patient should have the right to make medical determinations regardless of whether the determination is rational or reasonable. Gouse v. Cassel, 532 Pa. 197, 615 A.2d 331, 335 (1992). Opponents, however, focus on the unfairness of allowing the issue of causation to turn on the credibility of the hindsight of a person seeking recovery after experiencing a most undesirable result. Sard v. Hardy, 281 Md. 432, 379 A.2d 1014, 1025 (1977). “Patients cannot divorce their re-created decision process from hindsight.” F. Rozovsky, Consent to Treatment, § 1.13.4, 62-63 (1984). Accordingly, the subjective test potentially places the physician in jeopardy of the patient’s hindsight and bitterness. Sard, 379 A.2d at 1025. Moreover, the adoption of a subjective standard could preclude recovery in an informed consent case in which the patient died as a result of an unforewarned collateral consequence. Id.

Objective Standard

The majority 1 approach or the so-called objective standard emanates from the seminal decision in Canterbury v. Spence, 464 F.2d 772 (D.C.Cir.1972). In Canterbury, the court held that causation in informed consent cases is better resolved on an objective basis “in terms of what a prudent person in the patient’s position would have decided if suitably informed of all perils bearing significance.” Id. at 791. The objective view recognizes that neither the plaintiff nor the fact-finder can provide a definitive answer as to what the patient would have done had the patient known of the particular risk prior to consenting to the procedure or treatment. Id. at 790. Accordingly, the patient’s testimony is relevant under an objective approach, but the testimony is not controlling. Id. at 791.

*123 Modified Objective Standard

The modified objective standard was first recognized in Leyson v. Steuermann, 5 Haw.App. 504, 705 P.2d 37 (1985). In Leyson, the Hawaii Court of Appeals attempted to balance patient’s right to self-determination with the concerns espoused in Canterbury of subjecting a physician to a patient’s bitterness or hindsight following an undesirable result. The resulting test determined causation “from the viewpoint of the actual patient acting rationally and reasonably.” Id. at 47, n. 10.

Approximately ten years after the inception of the modified approach, the approach was declared to be onerous in application. In Bernard v. Char, 79 Hawaii 362, 903 P.2d 667 (1995), the Hawaii Supreme Court elaborated that:

In its effort to achieve the desired result of combining the objective and subjective standards, the modified objective standard injects at least one extra level of complexity into the causation analysis. Under the objective standard, the fact-finder must suspend his or her own viewpoint and step into the viewpoint of a reasonable person to objectively assess the plaintiff-patient’s decision to undergo treatment. Under the subjective standard, the factfinder must simply assess the credibility of the plaintiff-patient when he or she invariably asserts that he or she would have declined treatment with proper disclosure. Under the “modified objective standard,” however, the factfinder must first suspend his or her viewpoint, then place himself or herself in the mind of the actual patient, and, then, while maintaining the viewpoint of the actual patient, try to determine what the actual patient would have decided about the proposed medical treatment or procedure, if the actual patient were acting rationally and reasonably.

Id. at 673. Accordingly, the modified approach was abandoned in favor of the objective standard.

[Djespite being well-intentioned, [it] exacts too much of a cost in the form of added complexity in seeking to solve problems associated with the preexisting objective and subjective standards while at the same time remaining faithful to the laudable purposes behind such standards.

Id. The Court held: (1) that the objective standard provided “a better, simpler, and more equitable analytical process;” and (2) that the objective standard ultimately addressed the concerns which prompted the creation of the modified test.

CONCLUSION

We agree with the majority of jurisdictions having addressed this issue and hold that the objective approach is the better approach. The objective approach circumvents the need to place the fact-finder in a position of deciding whether a speculative and perhaps emotional answer to a purely hypothetical question shall dictate the outcome of the litigation. The objective standard is consistent with the prevailing standard in negligence cases which measures the conduct of the person in question with that of a reasonable person in like circumstances. Restatement (Second) of Torts § 283, p. 12 (1965); see also 1 S. Pegalis & H. Wachsman, American Law of Medical Malpractice, § 2.15, 103-104 (1980) (criticizing subjective test as being out of step with general negligence concepts). The objective test provides a realistic framework for rational resolution of the issue of causation. We, therefore, believe that causation may best be assessed in informed consent cases by the finder of fact determining how nondisclosure would affect a reasonable person in the plaintiffs position.

We also are of the opinion that the objective test appropriately respects a patient’s right to self-determination. The finder of fact may consider and give weight to the patient’s testimony as to whether the patient would have consented to the procedure upon full disclosure of the *124 risks. When applying the objective standard, the finder of fact may also take into account the characteristics of the plaintiff including the plaintiffs idiosyncrasies, fears, age, medical condition, and religious beliefs. Bernard v. Char, 79 Hawai'i 362, 903 P.2d 667, 674 (1995); Fain v. Smith, 479 So.2d 1150, 1155 (Ala.1985); Backlund v. University of Washington, 137 Wash.2d 651, 975 P.2d 950 (1999). Accordingly, the objective standard affords the ease of applying a uniform standard and yet maintains the flexibility of allowing the finder of fact to make appropriate adjustments to accommodate the individual characteristics and idiosyncrasies of an individual patient. We, therefore, hold that the standard to be applied in informed consent cases is whether a reasonable person in the patient’s position would have consented to the procedure or treatment in question if adequately informed of all significant perils.

In applying the objective standard to the facts of this case, we agree with the Court of Appeals that the jury should not have been precluded from deciding the issue of informed consent. Under the objective analysis, the plaintiffs testimony is only a factor when determining the issue of informed consent. The dispositive issue is not whether Ms. Ashe would herself have chosen a different course of treatment. The issue is whether a reasonable patient in Ms. Ashe’s position would have chosen a different course of treatment. The jury, therefore, should have been allowed to decide whether a reasonable person in Ms. Ashe’s position would have consented to the radiation therapy had the risk of paralysis been disclosed.

The judgment of the Court of Appeals reversing the trial court is affirmed. The case is remanded for a new trial consistent with this opinion. Costs of the appeal to the Court of Appeals shall be as previously taxed; costs of the appeal to this Court shall be taxed against the plaintiff for which execution may issue if necessary.