Whether a patient who suffers an adverse medical outcome may bring a common-law medical negligence claim for the negligent loss of a substantial chance of a better outcome, even if proper care was less than 50 percent likely to prevent that outcome.
Holding
Yes. The loss of a substantial chance of a better medical outcome can itself be a compensable injury in an Oregon common-law medical malpractice claim. Smith’s alleged loss of a 33 percent chance was sufficient to state such a claim.
Reasoning
A medical negligence plaintiff must prove, more likely than not, that the defendant’s breach caused the claimed injury. Smith did not claim that proper treatment probably would have prevented his brain damage. Instead, he identified the lost opportunity for a better outcome as the injury. He must still prove, under the ordinary causation standard, that defendants’ negligence caused that loss.
Earlier Oregon decisions did not foreclose this claim. A prior wrongful-death decision required proof that negligence caused death because the statute made death the compensable injury. Other decisions addressed causation of a plaintiff’s eventual physical condition, not whether a lost chance could itself be an injury under the common law.
Treating a lost chance as an injury avoids leaving patients without a remedy solely because their prospects were less than even before treatment. The physician’s alleged negligence deprived Smith of the opportunity that proper care might have preserved—and made it impossible to know whether he would have been among the patients who benefited.
A chance below 50 percent is not necessarily too speculative to prove. Reliable medical evidence may establish both the likelihood of a better outcome with proper care and the extent to which negligence reduced it; defendants may challenge that evidence. The court concluded that Smith’s alleged 33 percent chance was substantial, without deciding whether every loss-of-chance claim must meet a separate substantiality threshold.
A plaintiff must plead the percentage and quality of the lost chance with specificity and must have suffered an adverse medical outcome. Damages may account for physical and emotional harm attributable to the lost chance, but must reflect the value of that chance rather than automatically award the full damages associated with the adverse outcome.