Published 1/1/2010
S. Jay Jayasankar, MD; Sarah Elisabeth Curi, JD, MPH

“Loss of chance” doctrine in medical liability

In two landmark decisions in 2008, the Supreme Judicial Court (SJC) of Massachusetts ruled that state law permits recovery for a “loss of chance” in medical malpractice cases. As a result, Massachusetts plaintiffs may now receive compensation for a reduction, resulting from a doctor’s negligence, in their “chance” for a more favorable outcome, even if that chance is less than 50 percent.

Traditionally, if the jury finds a physician’s negligence was the probable cause of the patient’s death or injury (defined as greater than 50 percent chance, or by a “preponderance of the evidence”), the patient is awarded the entire damages (eg. projected life-expectancy earnings). If, however, the jury concludes there is less than a 50 percent chance or no preponderance of the evidence that malpractice caused the injury, the plaintiff receives nothing.

The first successful “loss of chance” case
In 1995, Dr. Neil Birnbaum, a board-certified internist and the patient’s primary physician, prescribed antacids for 42-year-old Kimiyoshi Matsuyama, who had had gastric symptoms since 1988. In 1999, Dr. Birnbaum ordered tests that revealed an adenocarcinoma of the stomach. The patient died of the cancer 5 months later at the age of 46.

The estate’s attorney argued that because of the doctor’s negligence, Mr. Matsuyama lost the chance to have timely testing and treatment that might have cured him. The trial court jury decided that Mr. Matsuyama’s chance of survival was about 37.5 percent at the time of the physician’s negligence and awarded the estate $160,000 for pain and suffering and $328,125 (amended to $281,310) for loss of chance (37.5 percent of the full damage, valued at $875,000).

Dr. Birnbaum’s appeal contended that adopting the loss of chance doctrine would upend the traditional preponderance of evidence standard, alter the burden of proof in favor of the plaintiff, and generally increase malpractice suits.

A new theory of injury
In affirming the lower court decision, the SJC stated that loss of chance is adopted “not as a theory of causation, but as a theory of injury.” The established test for malpractice would remain unchanged— the plaintiff would still have to establish that the physician’s breach of the standard of care resulted in the patient’s loss of chance by the traditional preponderance of the evidence standard.

The SJC reasoned that traditionally, an otherwise successful plaintiff could be compensated fully if the chance of a favorable outcome was 51 percent and receive nothing if it was 49 percent. Thus, the “all-or-nothing rule” provided a “blanket release from liability for doctors and hospitals any time there was less than a 50 percent chance of survival, regardless of how flagrant the negligence.”

The SJC explained that if the physician’s breach of duty destroyed or diminished the patient’s chance of survival or better outcome, the physician “deprived the patient of something of value” for which the patient deserved compensation as a matter of “fairness.”

To advance the “fundamental aims of tort law”—loss-sharing, deterrence, and compensation—and to comport with established statutes, Massachusetts adopted the loss of chance doctrine for injury but left intact the preponderance of evidence standard for proof of causation. The damages would be proportionate to the percentage loss of chance for the better outcome.

Narrow focus
The SJC emphasized that this new doctrine applies only to medical malpractice cases, which “are particularly well suited to [its] application” for the following reasons:

  • the availability of reliable expert evidence establishing loss of chance
  • the doctor-patient relationship, which has, at its heart, the concept that the physician will take every reasonable measure to obtain an optimal outcome for the patient
  • the fact that patients often have a less than even chance of survival or of achieving a better outcome when they first see a physician
  • the fact that failing to recognize loss of chance “forces the party who is the least capable of preventing the harm to bear the consequences of the more capable party’s negligence.”

In its summary, the SJC noted that “whatever difficulties may attend recognizing loss of chance as an item of damages in a medical malpractice action, these difficulties are far outweighed by the strong reasons to adopt the doctrine.” It added “precisely what yardstick to use to measure the reduction in the [patient’s] prospects for survival—life expectancy, 5-year survival, 10-year survival, and so on—is a question on which the law must inevitably bow to some extent to the shape of the available medical evidence in each particular case.”

The second case
In the second case, Mary Jane Renzi, age 48, visited internist Dr. Lavonne Veatch in December 1993 for an annual physical examination. Dr. Veatch noted her breasts to be multinodular. A mammogram in January 1994 was read as normal. In December 1994 Ms. Renzi was diagnosed with hidradenitis in her left axilla. A mammogram performed in January 1995 was read by Dr. Santiago Paredes as unchanged.

In August 1995, because of continued hidradenitis and tenderness in the left breast, a mammogram and needle biopsy were performed that revealed infiltrating ductal carcinoma with lymph node involvement. Ms. Renzi underwent radical mastectomy, radiation, chemotherapy, hormone therapy, and bone marrow transplant, and died 4 years later.

After Ms. Renzi’s death, her estate sued both doctors for malpractice. Dr. Veatch settled before the verdict. The trial court jury found that Dr. Paredes’ negligence was not a substantial contributing factor in causing Ms. Renzi’s death, but that it was a substantial contributing factor in causing her loss of a substantial chance to survive and awarded damages for the latter.

The SJC issued its decision on the same day as in the Matsuyama case and referred to the reasoning in that case in affirming all the findings in the Renzi case. The SJC remanded the case for a new trial to establish the amount of damages to be calculated proportionate to the amount of chance lost. The SJC held that even if the jury did not find the doctor liable for wrongful death, the plaintiff could recover for the loss of chance.

The impact
Massachusetts is just one of several states that have adopted a loss of chance theory. The SJC explained that “medical science has progressed to the point that physicians can gauge a patient’s chances of survival to a reasonable degree of medical certainty, and indeed routinely use such statistics as a tool of medicine.” Further, the SJC stated “the availability of such expert evidence on probabilities of survival makes it appropriate to recognize loss of chance as a form of injury...”

Chance and loss of chance can readily be expressed in percentages in oncology (albeit often broadly). Advances in and wider use of medical informatics are bound to expand this option into other fields. Although this novel doctrine does not create any new duty or alter any standard of care, it does establish another theory for physician liability. Arguably, it adds to the malpractice pressure that promotes the practice of defensive medicine raising healthcare costs.

This risk for additional liability demands no specific patient care skills or processes for prevention, but it does serve to remind physicians of the principles of quality care, empathic relations, and sound processes. For example, a system for ensuring prompt review of test and consultation results, informing patients and acting further, and recording and minimizing any delays by patients or extraneous factors will improve care and, in turn, influence the scales that assign responsibility.

The hope
Although consideration of fairness in specific instances may drive the creation of theories of injury such as loss of chance, there is urgent need for more fundamental and meaningful medical professional liability reform to enhance safety and equity for all patients. Effective reform should achieve the following goals:

  • help physicians to openly share their experiences and information to improve patient safety and to engage in empathic dialogue with injured patients
  • fairly and promptly compensate any one injured from medical negligence
  • minimize the intensity of the adversarial system through alternate resolution systems

S. Jay Jayasankar, MD, is a member of the AAOS Medical Liability Committee and editor of Orthopaedic Risk Manager for AAOS Now. Sarah Elisabeth Curi, JD, MPH, is a healthcare attorney who also teaches courses in American healthcare law and biomedical ethics at Brandeis University.

Editor’s note: Articles labeled Orthopaedic Risk Manager are presented by the Medical Liability Committee under the direction of contributing editor S. Jay Jayasankar, MD.

Articles are provided for general information and are not legal advice; for legal advice, consult a qualified professional.

E-mail your comments to feedback-orm@aaos.org or contact this issue’s contributors directly.


  1. Matsuyama v. Birnbaum, 890 N.E.2d 819 (Mass. 2008)
  2. Herskovits v. Group Health Coop. of Puget Sound, 99 Wash. 2d 609, 614 (1983).
  3. The SJC offered the following illustration “suppose in a wrongful death case that a jury found, based on expert testimony and the facts of the case, that full wrongful death damages would be $600,000 (step 1), that the patient had a 45% chance of survival prior to the medical malpractice (step 2), and that the physician's tortious acts reduced the chances of survival to 15% (step 3). The patient's chances of survival were reduced 30% (i.e., 45% minus 15%) due to the physician's malpractice (step 4), and the patient's loss of chance damages would be $600,000 multiplied by 30%, for a total of $180,000 (step 5).” (References omitted.) Matsuyama v. Birnbaum, 890 N.E.2d 819 (Mass. 2008)
  4. K.S. Abraham, Forms and Functions of Tort Law 117-118 (3d ed. 2007)
  5. Restatement (Third) of Torts: Liability for Physical Harm § 26 comment n (Proposed Final Draft No.1, 2005) comment n (Draft Restatement)
  6. Renzi v. Paredes, 890 N.E.2d 817 (Mass. 2008)
  7. Ten state courts have refused to adopt the loss of chance doctrine. The remaining 18-20 state courts have not addressed it or explicitly left the issue open.
  8. Kessler DP, McClellan MB. How liability law affects medical productivity. Journal of Health Economics 2002;21:93155
  9. AAOS Position Statement on Medical Liability Reform Accessed on October 26, 2009