Evaluation of medical practices

Evaluation of the efficacy of a medical intervention requires valid measurements of both its benefits and risks as compared to those of alternative forms of management. The requisite measurements are more difficult to make than this simple description suggests, and the accumulation of information is further inhibited by certain characteristics of our pattern of health care. These features include, for example, discontinuous care by a variety of unrelated providers, inadequate records, the autonomy of physicians as decision-makers, financial disincentives, ambiguities in what we mean by "experimental" and "accepted" forms of therapy, and failure to see continuing evaluation as a necessary component of the cost of providing good medical care. Although no single change will solve all the problems of evaluation, several offer promise of improving our ability to choose from among medical interventions those most likely to be useful.