The "lost chance" recognized in Ferrell v. Rosenbaum, 691 A.2d 641 (D.C. 1997) was thus the opportunity for the plaintiff to avail herself of a medical procedure with a high likelihood (a 70-90 percent chance) of success if carried out. Even if Ferrell were regarded as easing the burden of proof on causation in some medical malpractice cases, however, we are not convinced that a similar relaxation of proof should apply here. In Ferrell the court carefully limited its consideration of lost chance to "a case such as this involving negligent treatment of a potentially fatal condition," 691 A.2d at 651, in turn illustrating the situation where "'the harm alleged appears to have been brought about by two or more concurrent causes.'" Id. (quoting Daniels, 185 U.S. App. D.C. at 92, 566 F.2d at 757). In such a case, the lost chance doctrine may well make sense because of the difficulty of differentiating between the consequences of a pre-existing condition and those flowing from the negligent failure to ameliorate it. See, e.g., Hardy v. Southwestern Bell Tel. Co., 910 P.2d 1024, 1026 (Okla. 1996) (explaining that the "loss of chance" theory where applied has typically been limited to a case where "negligence increases the risk of harm by aggravating the effect of a pre-existing condition or risk and/or taking away whatever chance of recovery existed"). To apply the loss of chance theory to cases such as these would virtually collapse the limitations that our decisions have set to the reach of proximate causation. 8 Cases such as Talley v. Varma, supra, demonstrate that any such relaxation of the standard of proof on causation must be effected by the entire court, and not a division. See M.A.P. v. Ryan, 285 A.2d 310, 312 (D.C. 1971). Still another problem with applying the "loss of chance" doctrine is its analytical kinship "with the allocation of damages based on comparative fault, regardless of whether the physician's negligence is pegged above or below 50 percent in terms of proximate causation." Kilpatrick v. Bryant, 868 S.W.2d 594, 615 (Tenn. 1993) (Daughtrey, J., concurring in part and dissenting in part). This jurisdiction, of course, has not adopted comparative fault. Instead, as do the courts of Maryland, we follow the rule that: traditional tort law is based on probabilities. If a patient had a 49% chance of dying from an injury or disease and if the patient was negligently treated and dies, full recovery will be permitted because, absent the negligence, it was more likely than not that the patient would have survived. Based on the 51% probability of surviving the injury or disease, we exclude the injury or disease as the cause of death. Damages are not reduced by the fact that there was a strong possibility that the patient would have died absent the negligence. Conversely, if the patient had a 51% chance of dying from an injury or disease, and was negligently treated and died, it was probably the pre-existing medical condition, not the negligence, that killed the patient, and there is no recovery. Damages must be proven by a preponderance of the evidence. Damages are not proven when it is more likely than not that death was caused by the antecedent disease or injury rather than the negligence of the physician. Fennell, supra note 5, 580 A.2d at 214.