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Loss of chance doctrine, medical malpractice

Subject Categories

Insurance Law | Law | Torts


The loss of chance doctrine in medical malpractice cases holds that when a doctor is responsible for reducing a patient's chance of survival by some percentage, the patient (or the patient's estate) should be compensated by the doctor for that percentage loss. Compensation is often determined by multiplying the value of a patient's life by the lost chance. This paper investigates psychological factors that my affect a legal decision maker's evaluation of damage awards in loss of chance cases. A paper and pencil experiment and a large-scale mock jury study (the latter using videotaped trials) are conducted to investigate the following questions: (1) Are identical lost chance percentages evaluated differently as a function of where they fall on the probability scale? (2) Are "lost chances to live" evaluated differently from "increased risks to die?" (3) Is lost chance reasoning more likely to be invoked for cases that have a large number of plaintiffs (i.e., class actions)? and (4) Does group deliberation affect the magnitude or frequency of lost chance damage awards?