OPINION
DROWOTA, Justice.In this medical malpractice case, the Plaintiffs, Sandra and William Kilpatrick, have appealed from a decision of the Court of Appeals affirming the grant of summary judgment in favor of Dr. James W. Bryant, Defendant-Appellee. We granted the Plaintiffs’ Rule 11 application to decide whether a cause of action for “loss of chance” is cognizable in Tennessee. For the reasons discussed below, we decline to recognize such a cause of action and hold that there can be no liability in a medical malpractice case for negligent diagnosis or treatment that decreases a patient’s chances of avoiding death or other adverse medical condition where the death or adverse medical condition would probably have occurred anyway.
I.
The Plaintiffs alleged in their complaint that on May 18, 1987, Dr. Bryant examined Sandra Kilpatrick at which time a lump was detected in her right breast. Dr. Bryant ordered a mammogram which was performed on May 21, 1987, by Dr. Thipavan Boone. Dr. Boone interpreted the xeromammogra-phy films and stated that no definite outline of a mass or indication of malignancy was seen. Mrs. Kilpatrick avers that Dr. Bryant informed her that the mammogram results were negative. Approximately four months later, in September, Mrs. Kilpatrick was examined by another physician who did a biopsy. Cancer was detected and Mrs. Kilpa-trick underwent a right radical mastectomy a month later for removal of the cancer of the right breast.
The Plaintiffs sued Dr. Bryant and the radiologists who performed the mammogram, although the radiologists were later voluntarily dismissed from the case. The Plaintiffs claim that Dr. Bryant was negligent in the treatment of Mrs. Kilpatrick in relying *597upon the findings of the radiologists and in failing to inform her of the need to seek follow-up care. Specifically, their complaint alleges that
[t]he Defendant, James W. Bryant, was negligent and careless in the treatment of the Plaintiff, Sandra K. Kilpatrick, inasmuch as he should not have relied totally upon the findings of the radiologists, and that further he failed to even suggest the need for follow-up examination or further consultation; that likewise, as a direct and proximate result of his negligence, Plaintiff, Sandra K. Kilpatrick, suffered more serious complications and a general worsening of her cancerous condition as a result of her cancer going undetected for approximately four months.
It is further claimed by the Plaintiffs that Dr. Bryant’s negligence required Mrs. Kilpa-trick to seek additional medical treatment, suffer loss of earning capacity and enjoyment of life, experience pain and disablement, and has made her medical condition worse than it would otherwise be. Mr. Kilpatrick seeks recovery for loss of consortium.
In his answer, Dr. Bryant denied that his conduct fell below the required standard of care. He also denied that the physical condition of Mrs. Kilpatrick resulted from any violation of the standard of care by him. Dr. Bryant filed a motion for summary judgment on the basis that the Plaintiffs failed to present evidence establishing the elements of a medical malpractice action as set forth in T.C.A. § 29-26-115. In opposition to Dr. Bryant’s motion for summary judgment, the Plaintiffs filed the affidavit of Dr. James A. Schell, which stated that he was familiar with the recognized standard of care for physicians in Memphis and the care and treatment of patients with suspected breast cancer. He further stated that Dr. Bryant faded to meet the accepted standard of medical care. Dr. Schell’s affidavit addressed only the issues of the standard of care and its alleged violation by Dr. Bryant. The Plaintiffs also filed the affidavit of Dr. Lee R. Morisy, Mrs. Kilpa-trick’s subsequent treating physician. Dr. Morisy stated that he operated on Mrs. Kil-patrick and performed the right radical mastectomy. The only proof concerning causation in this case is found in the affidavit of Dr. Morisy. He states that
I am of the medical opinion, based on a reasonable degree of medical certainty, that the delay of four (4) months in the operation performed increased the likelihood of Mrs. Kilpatrick suffering irreparable damage.
The trial court granted Dr. Bryant’s motion for summary judgment and dismissed the case. The Court of Appeals affirmed on the basis that the physicians’ affidavits supplied by the Plaintiffs in opposition to the motion for summary judgment did not establish that Mrs. Kilpatrick had suffered injuries that would not otherwise have occurred but for Dr. Bryant’s negligence. The intermediate court explained that
[i]n the case at bar, Plaintiffs’ proof is from the affidavit of Dr. Morisy which states that the ‘delay of four (4) months ... increased the likelihood of Mrs. Kilpatrick suffering irreparable damage.’ This proof deals with future effect resulting from the action of the physician. The affidavit does not state the delay of four months caused Mrs. Kilpatrick to suffer irreparable damage. It merely states that there is a likelihood or probability that the delay would cause irreparable damage.
Accordingly, the Court of Appeals affirmed the dismissal of the case.
II.
A proper resolution of the present controversy requires that it be viewed in the context of certain well-established principles of tort law. Because this case centers on medical malpractice, the starting point is T.C.A. § 29-26-115(a). According to this statute, the plaintiff in a medical malpractice case has the burden of proving the following:
(1) The recognized standard of acceptable professional practice in the profession and the specialty thereof, if any, that the defendant practices in the community in which he practices or in a similar community at the time the alleged injury or wrongful action occurred;
(2) That the defendant acted with less than or failed to act with ordinary and *598reasonable care in accordance with such standard; and
(3) As a proximate result of the defendant’s negligent act or omission, the plaintiff suffered injuries which would not otherwise have occurred.
This statute codifies the common law elements of negligence — duty, breach of duty, causation, proximate cause, and damages. Cardwell v. Bechtol[ 724 S.W.2d 739, 753 (Tenn.1987); Dolan v. Cunningham, 648 S.W.2d 652, 654 (Tenn.App.1982). No claim for negligence can succeed in the absence of any one of these elements. Bradshaw v. Daniel, 854 S.W.2d 865, 869 (Tenn.1993).
Cases involving the “loss of chance” theory of recovery necessarily focus on the elements of causation and proximate cause. See, e.g., Kramer v. Lewisville Memorial Hosp., 858 S.W.2d 397 (Tex.1993). Causation, or cause in fact, means that the injury or harm would not have occurred “but for” the defendant’s negligent conduct. See Caldwell v. Ford Motor Co., 619 S.W.2d 534, 543 (Tenn.App.1981); Wyatt v. Winnebago Industries, Inc., 566 S.W.2d 276, 280 (Tenn.App.1977). Once it is established that the defendant’s negligent conduct was, in point of fact, the actual cause of the plaintiffs injury or harm, the focus then becomes whether the policy of the law will extend responsibility for that negligent conduct to the consequences that have occurred. As this Court stated in Doe v. Linder Const. Co., Inc., 845 S.W.2d 173 (Tenn.1992), “legal responsibility must be limited to those causes which are so closely connected with the result and are of such significance that the law is justified in imposing liability. Some boundary must be set....” Doe, 845 S.W.2d at 181 (quoting Prosser and Keeton, The Law of Torts 264 (5th ed. 1984)). Fixing this boundary of liability is the purpose underlying the element of proximate cause. Proximate cause
is merely the limitation which the courts have placed upon the actor’s responsibility for the consequences of the actor’s conduct.... [T]he consequences of an act go forward to eternity, and the causes of an event go back to the dawn of human events, and beyond. Any attempt to impose responsibility upon such a basis would result in infinite liability....1
Id.
Causation and proximate cause are distinct elements of negligence, and both must be proven by the plaintiff by a preponderance of the evidence. Bradshaw, 854 S.W.2d at 869; McClenahan v. Cooley, 806 S.W.2d 767, 774 (Tenn.1991); Smith v. Gore, 728 S.W.2d 738, 749 (Tenn.1987). “Causation (or cause in fact) is a very different concept from that of proximate cause. Causation refers to the cause and effect relationship between the tortious conduct and the injury. The doctrine of proximate cause encompasses the whole panoply of rules that may deny liability for otherwise actionable causes of harm.” King, Causation, Valuation, and Chance in Personal Injury Torts Involving Preexisting Injuries and Future Consequences, 90 Yale L.J. 1353, 1355 n. 7 (1981). Thus, proximate cause, or legal cause, concerns a determination of whether legal liability should be imposed where cause in fact has been established. McKellips v. Saint Francis Hosp., 741 P.2d 467 (Okl.1987). “Cause in fact, on the other hand, deals with the ‘but for’ consequences of an act. ‘The defendant’s conduct is a cause of the event if the event would not have occurred but for that conduct.’ ” Id. at 470 (quoting Prosser and Keeton, The Law of Torts 266 (5th ed. 1984)).
The critical issue in this appeal, as in all loss of chance cases, is whether the Plaintiffs have failed, as a matter of law, to establish the existence of causation, i.e., that the purported medical malpractice actually caused the harm complained of. McKellips, 741 P.2d at 470-71. This question dominates because the rule requiring causation be proven by a preponderance of the evidence dictates that Plaintiffs demonstrate that the *599negligence more likely than not caused the injury. Lindsey v. Miami Dev. Corp., 689 S.W.2d 856, 861 (Tenn.1985) (“[pjlaintiff must introduce evidence which affords a reasonable basis for the conclusion that it is more likely than not that the conduct of the defendant was a cause in fact of the result”). To be sure, the mere occurrence of an injury does not prove negligence, and an admittedly negligent act does not necessarily entail liability. Doe, 845 S.W.2d at 181. Even when it is shown that the defendant breached a duty of care owed to the plaintiff, the plaintiff must still establish the requisite causal connection between the defendant’s conduct and the plaintiffs injury. Id. (“Proof of negligence without proof of causation is nothing”).
III.
In the context of medical malpractice, the “loss of chance” doctrine, sometimes called the “increased risk of harm” doctrine, permits a recovery where the delay in proper diagnosis or treatment of a medical condition results in the patient being deprived of a less than even chance of surviving or recovering. See Loss of Chance in Medical Malpractice Cases, 20 Mem.St.U.L.Rev. 81, 91 (1989). Stated another way, the patient has a cause of action for the increase in the risk of harm or loss of a better chance of surviving, recovering, or a more favorable result. 90 Yale L.J. at 1365. “Traditionally, the concept of ‘loss of chance’ has been employed in the situation where the possibility of a more favorable outcome has been denied by the defendant’s negligence, but where the plaintiff was already in peril of injury because of an underlying condition at the time.” Price, Causation-The Lord’s Lost Chance?, 38 Int’l and Comp.L.Q. 735, 735-36 (Oct. 1989); see also Manning v. Twin Falls Clinic and Hosp., 122 Idaho 47, 51 n. 2, 830 P.2d 1185, 1189 n. 2 (1992) (increased risk of harm refers to whether the negligence of the plaintiff has increased the plaintiffs risk of harm while loss of chance refers to whether that negligence deprived the plaintiff of a chance or opportunity for a recovery, and cases analyzing the terms use them interchangeably). The doctrine applies to those situations in which the plaintiff suffers from a preexisting medical condition, and this condition is such that he has less than a 51 percent chance of recovering even with optimal medical care. The negligent physician is thus subject to liability to the extent that he tortiously contributes to the harm by permitting the preexisting condition to progress, or by accelerating its harmful effects. 90 Yale L.J. at 1360.
The loss of chance doctrine has its genesis in Hicks v. United States, 368 F.2d 626 (4th Cir.1966). The Fourth Circuit in Hicks held that a physician breached the standard of care by failing to diagnose an intestinal obstruction from which the patient died. The proof demonstrated that it was more likely than not that the patient would have survived had she not been negligently diagnosed by the defendant. Despite this proof, the court, in dicta, stated:
When a defendant’s negligent action or inaction has effectively terminated a person’s chance of survival, it does not lie in the defendant’s mouth to raise conjectures as to the measure of the chances that he has put beyond the possibility of realization. If there is any substantial possibility of survival and the defendant has destroyed it, he is answerable.
Hicks, 368 F.2d at 632. Primarily from this quoted language, several courts, as explained below, have fashioned the loss of chance doctrine which the Plaintiffs in the instant case ask this Court to adopt. We note, however, that the Fourth Circuit has recently reviewed its Hicks decision in Hurley v. United States, 923 F.2d 1091 (4th Cir.1991), in which it referred to the quoted language above as “dicta which [has] precipitated misunderstanding throughout the courts.” Id. at 1093. The court in Hurley held that Hicks was not intended to change traditional notions of causation in medical malpractice cases, and rejected the loss of chance doctrine as a viable cause of action — thereby negating the widely held view of Hicks. Id. at 1095, 1099. The court reinstated the traditional standard for proving causation which requires a showing of probability of survival or recovery of greater than 50 percent absent the defendant’s negligence.
*600Prior to the Fourth Circuit’s clarification of Hicks in the Hurley decision, several jurisdictions seized upon the language quoted above to relax the traditional standard of causation, i.e., more likely than not, and have held that the destruction of a lost opportunity for survival or recovery will satisfy the standard for causation even if the plaintiffs chance of avoiding the ultimate harm was improbable, i.e., less than 50 percent. Hence, the key inquiry presented by these types of cases is whether there can be “liability for negligent treatment that decreases a patient’s chance of avoiding death or other medical conditions [because] the adverse result probably would have occurred anyway.” Kramer, 858 S.W.2d at 398. There are now many cases coming down on both sides of this question. See Annotation, Medical Malpractice: “Loss of Chance” Causality, 64 A.L.R.4th 10 (1987). The jurisdictions that have considered the issue can be placed into one of three general categories: (1) pure loss of chance, (2) loss of a substantial chance, and (3) the traditional approach to causation, sometimes referred to as the all-or-nothing approach, see 90 Yale L.J. at 1365.
(1).
As stated earlier, in many medical negligence cases, the patient’s medical condition is such that he has less than a 51 percent chance of survival or recovery even with optimal medical care. The traditional but for test of cause in fact prevents recovery under such circumstances because the patient’s condition would more likely than not be the same even if the defendant had not been negligent. The Texas Supreme Court, in a thoughtful opinion authored by Chief Justice Phillips, recently explained the problem as follows:
[Where] preexisting illnesses or injuries have made a patient’s chance of avoiding the ultimate harm improbable even before the allegedly negligent conduct occurs— i.e., the patient would die or suffer impairment anyway — the application of these traditional causation principles will totally bar recovery, even if such negligence has deprived the patient of a chance of avoiding the harm.
Kramer, 858 S.W.2d at 400 (emphasis in original). Several courts have viewed this result as unduly harsh and, consequently, have relaxed the traditional causation standard to allow recovery where the plaintiff proves the physician’s conduct deprived him of a possibility of a better medical result. Ten jurisdictions have adopted this pure form of loss of chance (or at least have not undertaken to limit the cause of action with “substantial chance” language). Voegeli v. Lewis, 568 F.2d 89 (8th Cir.1977) (applying South Dakota law); Thompson v. Sun City Comm. Hosp., 141 Ariz. 597, 688 P.2d 605 (1984); Richmond County Hosp. Auth. v. Dickerson, 182 Ga.App. 601, 356 S.E.2d 548 (1987); DeBurkarte v. Louvar, 393 N.W.2d 131 (Iowa 1986); Aasheim v. Humberger, 215 Mont. 127, 695 P.2d 824 (1985); Scafidi v. Seiler, 119. N.J. 93, 574 A.2d 398 (1990); Hamil v. Bashline, 481 Pa. 256, 392 A.2d 1280 (1978); Herskovits v. Group Health Coop., 99 Wash.2d 609, 664 P.2d 474 (1983); Thornton v. CAMC, 172 W.Va. 360, 305 S.E.2d 316 (1983); Ehlinger v. Sipes, 155 Wis.2d 1, 454 N.W.2d 754 (1990). Thus, for example, under the pure, form of loss of chance, a patient who faced a 95 percent chance of dying even with appropriate medical care would still have a cause of action against the physician who negligently deprived him of the 5 percent chance of survival.
(2).
In addition to the ten jurisdictions recognizing pure loss of chance as a viable theory of recovery, six more permit the cause of action but add the requirement that the negligence be shown to have reduced a “substantial chance” or “substantial possibility” or “appreciable chance” of a favorable end result given appropriate medical treatment. Jeanes v. Milner, 428 F.2d 598 (8th Cir.1970) (applying Arkansas law); Roberson v. Counselman, 235 Kan. 1006, 686 P.2d 149 (1984); Falcon v. Memorial Hosp., 436 Mich. 443, 462 N.W.2d 44 (1990); McKellips v. Saint Francis Hosp., 741 P.2d 467 (Okla.1987); Perez v. Las Vegas Medical Center, 107 Nev. 1, 805 P.2d 589 (1991); Kallenberg v. Beth Israel Hosp., 45 A.D.2d 177, 357 N.Y.S.2d 508 (1974). This approach is apparently de*601signed to prohibit claims where the plaintiff does not have a realistic basis for a favorable outcome even absent the defendant’s negligence. At the same time, “a health care provider will not be able to avoid responsibility for negligent conduct simply by saying that the patient would have died anyway, when that patient had a reasonable chance to live.” Perez, 805 P.2d at 593.
Courts allowing recovery for loss of chance view the compensable injury as the impaired or destroyed opportunity for a more favorable medical result, not the unfavorable result itself. .See, e.g., Falcon v. Memorial Hosp., 436 Mich. 443, 462 N.W.2d 44, 52 (1990). According to these courts, the interest which the law seeks to protect is the impaired or destroyed chance. Thompson v. Sun City Comm. Hosp., 141 Ariz. 597, 608, 688 P.2d 605, 616 (1984). When the injury itself is defined as the impaired or destroyed opportunity, the plaintiff can recover for that impaired or destroyed opportunity even though the chances of an ultimate, favorable medical result are 50 percent or less. Id. 462 N.W.2d at 53-54. The reason is that the causational link which the plaintiff must establish is between the defendant’s negligence and the impaired or destroyed opportunity, not between the negligence and the unfavorable medical result. Plaintiff, therefore, must prove that it is more probable than not that the defendant’s negligence was the cause in fact of the reduced opportunity for avoiding the ultimate, unfavorable outcome. Id. at 53.
(3).
Although several jurisdictions have decided to permit the cause of action for loss of chance, many others have either rejected loss of chance explicitly or have at least refused to allow recovery under the typical loss of chance scenario. See, e.g., Alfonso v. Lund, 783 F.2d 958 (10th Cir.1986); Gooding v. University Hosp., 445 So.2d 1015 (Fla.1984); Manning v. Twin Falls Clinic and Hosp., 122 Idaho 47, 830 P.2d 1185 (1992); Watson v. Medical Emergency Serv., 532 N.E.2d 1191 (Ind.App.1989); Walden v. Jones, 439 S.W.2d 571 (Ky.1968); Fennell v. Southern Maryland Hosp., 320 Md. 776, 580 A.2d 206 (1990); Clayton v. Thompson, 475 So.2d 439 (Miss.1985) and Ladner v. Campbell, 515 So.2d 882 (Miss.1987); Pillsbury-Flood v. Portsmouth Hosp., 128 N.H. 299, 512 A.2d 1126 (1986); Cooper v. Sisters of Charity, 27 Ohio St.2d 242, 272 N.E.2d 97 (1971); Sherer v. James, 290 S.C. 404, 351 S.E.2d 148 (1986); Kramer v. Lewisville Memorial Hosp., 858 S.W.2d 397 (Tex.1993); Blondel v. Hays, 241 Va. 467, 403 S.E.2d 340 (1991); see generally, Grody v. Tulin, 170 Conn. 443, 365 A.2d 1076 (1976) (defendant physicians were entitled to judgment as a matter of law where jury was called upon to speculate whether an earlier diagnosis and treatment of the patient’s cancer might have prolonged her life); Cornfeldt v. Tongen, 295 N.W.2d 638 (Minn.1980) (judgment notwithstanding the verdict should have been granted to the defendant physician, despite expert proof that surgery increased the risk of death to the patient with underlying liver disease, because the patient failed to show that it was more probable than not that but for the operation she would have recovered); Horn v. National Hosp. Ass’n, 169 Or. 654, 131 P.2d 455 (1944) (dismissal upheld where the delay in diagnosis was not shown to have resulted in harm that would not have occurred even if there had been no delay in diagnosis). Many of these courts raise the objection that “recognition of mere chance as a recoverable item of loss fundamentally contradicts the essential notion of causation.” Falcon, 462 N.W.2d at 58 (Riley, C.J., dissenting). The jurisdictions adhering to this view do so because plaintiffs ought to be required to show that the negligence more likely than not was the cause in fact of the unfavorable medical result. In other words, recovery is disallowed unless it can be shown that the plaintiff would not have suffered the physical harm but for the defendant’s negligence, i.e., that it is more probable than not (greater than 50 percent) that but for the negligence of the defendant the plaintiff would have recovered or survived. Id. at 47.
IV.
Returning to the case at bar, we must decide whether Plaintiffs have proven that the Defendant’s negligence caused “injuries which would not otherwise have occurred.” T.C.A. § 29-26-115(a)(3). As the *602Sixth Circuit recently noted in Boburka v. Adcock, 979 F.2d 424 (6th Cir.1992), a plaintiff in a medical malpractice case in Tennessee must “prove that it is more likely than not that the defendant’s negligence caused plaintiff to suffer injuries which would have not otherwise occurred.” Id. at 429.2 In this regard, we reaffirm our observations made in Lindsey, supra:
The plaintiff must introduce evidence which affords a reasonable basis for the conclusion that it is more likely than not that the conduct of the defendant was a cause in fact of the result. A mere possibility of such causation is not enough; and when the matter remains one of pure speculation or conjecture or the probabilities are at best evenly balanced, it becomes the duty of the court to direct a verdict for the defendant....
The plaintiff is not, however, required to prove the case beyond a reasonable doubt. The plaintiff need not negative entirely the possibility that the defendant’s conduct was not a cause and it is enough to introduce evidence from which reasonable persons may conclude that it is more probable that the event was caused by the defendant. than that it was not_ (Citation omitted). A doctor’s testimony that a certain thing is possible is no evidence at all. His opinion as to what is possible is no more valid than the jury’s own speculation as to what is or is not possible. Almost anything is possible, and it is thus improper to allow a jury to consider and base a verdict upon a ‘possible’ cause of death. (Citation omitted). The mere possibility of a causal relationship, without more, is insufficient. ...
Lindsey, 689 S.W.2d at 861-62. Thus, proof of causation equating to a “possibility,” a “might have,” “may have,” “could have,” is not sufficient, as a matter of law, to establish the required nexus between the plaintiff’s injury and the defendant’s tortious conduct by a preponderance of the evidence in a medical malpractice case. Causation in fact is a matter of probability, not possibility, and in a medical malpractice case, such must be shown to a reasonable degree of medical certainty. White v. Methodist Hosp. South, 844 S.W.2d 642, 648-49 (Tenn.App.1992).
As stated earlier, the Plaintiffs in the present case have established that there is a “likelihood” that the delay in proper diagnosis and treatment caused “irreparable damage.” The term “likelihood” can arguably be equated with a “probability.” See Webster’s Third New International Dictionary, Unabridged (Merriam Co.1971); Black’s Law Dictionary (6th ed.) (West 1990); contra White v. Methodist Hosp. South, supra (medical malpractice case equating likelihood with a possibility and therefore insufficient). Nonetheless, we are persuaded that the loss of chance theory of recovery is fundamentally at odds with the requisite degree of medical certitude necessary to establish a causal link between the injury of a patient and the tortious conduct of a physician. As stated earlier, a plaintiff in Tennessee must prove that the physician’s act or omission more likely than not was the cause in fact of the harm. Lindsey, 689 S.W.2d at 861. This requirement necessarily implies that the plaintiff must have had a better than even chance of surviving or recovering from the underlying condition absent the physician’s negligence. T.C.A. § 29-26-115(a)(3) plainly requires that the plaintiff suffer injury “which would not otherwise have occurred.” This statutory language is simply another way of expressing the requirement that the injury would not have occurred but for the defendant’s negligence, our traditional test for cause in fact. Although a plaintiff can recover for harm stemming from the aggravation of an existing illness, the plaintiff may not recover damages for the loss of a less than even chance of *603obtaining a more favorable medical result. The traditional test for cause in fact prevents reeovery because the patient’s condition would more likely than not be the same even if the defendant had not been negligent.
Accordingly, we hold that a plaintiff who probably, i.e., more likely than not, would have suffered the same harm had proper medical treatment been rendered, is entitled to no recovery for the increase in the risk of harm or the loss of a chance of obtaining a more favorable medical result. Chief Justice Riley of the Michigan Supreme Court, in her dissent in Falcon, supra, reflects our sentiments in this regard:
The ‘lost chance of survival’ theory urged by plaintiff represents not only a redefinition of the threshold of proof for causation, but a fundamental redefinition of the meaning of causation in tort law.
⅝ ⅝ ⅜ ⅜ ⅜ ⅜
Relaxing the causation requirement might correct a perceived unfairness to some plaintiffs who could prove the possibility that the medical malpractice caused an injury but could not prove the probability of causation, but at the same time could create an injustice. Health care providers could find themselves defending cases simply because a patient fails to improve or where serious disease processes are not arrested because another course of action could possibly bring a better result. No other professional malpractice defendant carries this burden of liability without the requirement that plaintiffs prove the alleged negligence probably rather than possibly caused the injury. We cannot approve the substitution of such an obvious inequity for a perceived one.
The lost chance of survival theory does more than merely lower the threshold of proof of causation; it fundamentally alters the meaning of causation.
The most fundamental premise upon which liability for a negligent act may be based is cause in fact. (Citation omitted.) An act or omission is not regarded as a cause of an event if the particular event would have occurred without it. (Citation omitted.) If the defendant’s acts did not actually cause the plaintiffs injury, then there is no rational justification for requiring the defendant to bear the cost of the plaintiffs damages,
* ⅜ * ⅜ * *
I believe it is unwise to impose liability on members of the medical profession in such difficult circumstances as those now before this Court. Rather than deterring undesirable conduct, the rule imposed only penalizes the medical profession for inevitable unfavorable results. The lost chance of survival theory presumes to know the unknowable.
Falcon, 462 N.W.2d at 61, 64-68. This is not to say that a plaintiff could not recover for an aggravation of his physical condition if he proves by a balance of probabilities that the negligent act or omission caused the harm when there was a better than even chance of recovering to begin with.
The dissent argues that Truan v. Smith, 578 S.W.2d 73 (Tenn.1979), an opinion which has been described as “ambiguous,” see Boburka v. Adcock, 979 F.2d 424 (6th Cir.1992), lends support for the adoption of loss of chance. It is true that in Truan the delay in proper diagnosis of the patient’s cancer increased the chances of or accelerated the patient’s death. Id. at 76. The Court, speaking through Justice Cooper, held that the evidence was sufficient to support a finding of negligence. Id. at 76-77. As conceded by the dissent, however, the dispositive issue in Truan was the physician’s negligence, not whether Tennessee should recognize a new cause of action for loss of chance. Thus, this Court was not called upon in Truan to examine and analyze the implications of adopting loss of chance. This Court did not cite, much less discuss, any cases or other authority even remotely related to loss of chance.
We decline to relax traditional cause in fact requirements and recognize a new cause of action for loss of chance. Accordingly, the Plaintiffs in this case are not entitled to recover damages for the impaired opportunity for. obtaining a more favorable medical result, the increase in the risk of harm, or the loss of a better chance of recovery or *604survival. Plaintiffs also seek damages for additional medical treatment, pain and suffering, loss of earning capacity, etc., directly attributable to the negligence of the Defendant. We conclude that these items of damages are recoverable because the Plaintiffs have shown that such damages would not have been incurred but for the Defendant’s negligence. Thus, the grant of summary judgment to the Defendant is sustained to the extent that it relates to the loss of chance or the increase in the risk of harm. Summary judgment as to the Plaintiffs’ claims for the other items of damages noted above is reversed. Costs are to be split evenly between the parties.
O’BRIEN, J., concurs. REID, C.J., files separate concurring opinion. DAUGHTREY and ANDERSON, JJ., file separate concurring and dissenting opinions.. In McClenahan v. Cooley, 806 S.W.2d 767 (Tenn.1991), we stated that the three-pronged test for proximate cause is: (1) the defendant's conduct must have been a substantial factor in bringing about the harm complained of; and (2) there is no rule or policy that should relieve the wrongdoer from liability because of the manner in which the negligence has resulted in the harm; and (3) the harm giving rise to the action could have reasonably been foreseen or anticipated by a person of ordinary intelligence and prudence. Id. at 775.
. The Sixth Circuit in Boburka concluded that Tennessee has not adopted the loss of chance theory of recovery in medical malpractice cases “but instead continues to follow traditional [causation and proximate cause] principles.” Id. at 431. Thus, the court determined that “[a]l-though Tennessee law requires this Court to draw a fine line between sufficient and insufficient proof of causation, we believe that a ‘significant chance' plainly falls below the 'more likely than not' standard. Rather, testimony in this case concerning a ‘significant chance' is comparable to testimony about a 'mere possibility’ rejected by the Tennessee Supreme Court...." Id. at 429.