information with ease and reliability. Considerable obstacles lie in the way of achieving these goals. Some relate to the content and structure of current health databases; others concern the difficulties and costs of creating and maintaining comprehensive databases. Furthermore, public health databases (e.g., those maintained by states) may themselves lack connections with one another. Other problems include the need to create longitudinal records to understand how patients fare ''in the system as a whole"; the need to adjust for important characteristics about patients' sociodemographic circumstances or health status (risk and severity adjustment); and the need to have information on the health of the population as a whole, not just of those who use the health system. Finally, the need for information on both end results (the outcomes) of care as well as on the processes of care poses great challenges to database developers.
The current push for health care reform has made clear to many that the success of reform options—as well as the ability to assess the effect of a reformed system on the health of the public—depends on access to the kinds of data that too often are unavailable.
Finally, as the reasons for creating large health databases mount, so do the possibilities that such databases (or, more correctly, their users) will do harm to patients, providers (institutions, physicians, and others), payers (government, private insurers, and corporations), and the public at large. The balance between the advantages of such databases and their potential for harm, or at least unfairness, to some groups is not yet clear, and the question of whether and how such entities ought to evolve has not been explored.
Recently, diverse groups of researchers, business leaders, and policymakers at state and regional levels have begun to develop databases intended to overcome some of the problems cited above and to permit increasingly sophisticated analyses of community health needs, practice patterns, costs, and quality of care. The interests that have prompted such action cover a broad range: the need to control business costs attributable to health benefits, the desire to use technological and computer applications to decrease administrative costs of processing insurance claims, the wish of experienced health services researchers to exploit the potential of health databases to evaluate and improve health care, the responsibility of community leaders to plan expansion and contraction of health care facilities and services across the nation, and the need to transmit medical history information for an increasingly mobile population.
Coincident with these interests are the greatly enhanced electronic capabilities for data management in many aspects of daily life. Comprehensive computer-based health data files can be easily linked and information from those files moved instantaneously. Many observers believe that an unparalleled opportunity exists to apply computer technologies creatively to