A claim for failure to obtain informed consent arises out of a "physician's duty to disclose to a patient information material to the decision whether to undergo treatment." (Arato v. Avedon (1993) 5 Cal.4th 1172, 1175.) In Cobbs v. Grant (1972) 8 Cal.3d 229, the Supreme Court held that "as an integral part of the physician's overall obligation to the patient there is a duty of reasonable disclosure of the available choices with respect to proposed therapy and of the dangers inherently and potentially involved in each." (Id. at p. 243.) The essential elements of a negligence claim arising from a physician's failure to obtain informed consent are: (1) performance of a medical procedure on the plaintiff; (2) the plaintiff did not give informed consent; (3) a reasonable person would not have given consent to the medical procedure if she or he had been fully informed of the results and risks of the medical procedure; (4) the plaintiff was harmed by a result or risk that should have been explained before the medical procedure was performed. (Id. at p. 245.) As stated in Cobbs v. Grant, supra, 8 Cal.3d 229, there must be a causal relationship between the failure to inform and the injury to the plaintiff. "Such causal connection arises only if it is established that had revelation been made consent to treatment would not have been given." (Id. at p. 245.) The patient may testify on this subject, "but the issue extends beyond his credibility. Since at the time of trial the uncommunicated hazard has materialized, it would be surprising if the patient-plaintiff did not claim that had he been informed of the dangers he would have declined treatment. Subjectively he may believe so, with the 20/20 vision of hindsight, but we doubt that justice will be served by placing the physician in jeopardy of the patient's bitterness and disillusionment." (Ibid.)