Medical management and managing medical care: the dilemma of evaluating new technology.

A unique computer simulation model has been developed to investigate the broad clinical and economic effects of changing risk factors for cerebrovascular and cardiovascular disease. The model can be used in countries where good input data are available to provide valuable information to aid policy decisions on medical care. This article describes the computer model, the sources of population and cost data, and the assumptions that must be made when a model of this type is used. The Swedish and U.S. populations are compared, and the results are expressed in years of life saved. Cost-effectiveness of intervention is assessed by combining economic and clinical data, and the most favorable cost-effectiveness ratios are found in the elderly population with high levels of serum cholesterol and diastolic blood pressure. In contrast, the costs per year of life saved in the younger population at low risk are comparatively high.