Reconsidering the Harvard Medical Practice Study Conclusions about the Validity of Medical Malpractice Claims

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Over fifteen years after first reporting to the State of New York, the Harvard Medical Practice Study (HMPS) continues to have a significant impact in medical malpractice policy debates. In those debates the HMPS has come to stand for four main propositions. First, "medical injury . . . accounts for more deaths than all other kinds of accidents combined" and "more than a quarter of those were caused by substandard care." Second, the vast majority of people who are injured as a result of substandard care do not file a claim. Third, "a substantial majority of malpractice claims filed are not based on provider carelessness or even iatrogenic injury." Fourth, "whether negligence or a medical injury had occurred . . . bore little relation to the outcome of the claims." In light of this continuing reliance on the HMPS and the follow-up closed claim study, this article reviews the evidence regarding their findings about the validity of medical malpractice claims. The results of this review are as follows: First, the finding that most eligible people do not bring medical malpractice claims is well supported and confirmed by other studies using both similar and very different research methods. Second, the finding that most medical malpractice claims are not based on either iatrogenic injury or provider negligence stands on a small and precarious empirical base. Indeed, the HMPS data are as likely to support a very different finding, namely that most malpractice claims are reasonably related to medical management injuries and provider negligence. Finally, the finding from the follow-up closed claim study rests on an even weaker base and is contradicted by a large body of research on closed medical malpractice claims. In fact, the research reviewed in part IIIB of this article suggests that the legal system filters out most of the weaker claims.


malpractice, health care, liability

Publication Title

Journal of Law, Medicine & Ethics

Publication Citation

33 J. L. Med. & Ethics 501 (2005)