Allocative medicine: efficiency, disease severity, and the payment mechanism.

Health care expenditures now account for nearly 10 percent of our gross national product, the highest share ever recorded. Concerned that this represents too many resources being devoted to health care, policymakers are searching for ways to control health care expenses. These include higher coinsurance and deductibles, measures to increase market shares of health maintenance organizations, and conversion from cost reimbursement to prospective reimbursement. These measures contain many incentives for patients and providers to alter use of health care services. However, aggregate resource use may or may not be lower and more efficient under these new programs. To determine whether limited resources would be devoted to maximizing the nation's health, incentives inherent in each policy option must be examined. This article describes a classification of types of disease and medical care outputs. The framework is then used to examine incentives offered to patients and providers by three alternative payment mechanisms--capitation, fee-for-service, and payment by diagnosis--regarding types of disease treated and mix of outputs produced. This type of analysis is required to select an appropriate payment mechanism for obtaining a socially acceptable allocation of resources.