'Black box' medical information systems. A technology needing assessment.

In a decade characterized by lessening regulation of other industries, the health services sector is increasingly scrutinized from all directions—from payers, purchasers, and patients. The rationale for this is evident from the annual litany of soaring health care costs and nagging doubts about the necessity and quality of many medical services. However, some efforts to rectify these worrisome trends through increasing information about the costs, appropriateness, quality, and hence "value" of health services have taken an ironic twist. They rely on information products about which very little information is known: the redoubtable "black box." In common parlance, a black box is "any unknown system, especially one considered solely in terms of input and output, without an understanding of its workings."1 In the health care sector, the term can apply to a variety of systems, such as those whose inputs are facts about patient demographics, diagnoses, symptoms, histories, physical examinations, laboratory