OBJECTIVE: To examine the cost-effectiveness of statins in relation to different measures of effectiveness, differences in efficacy among individual statins, and the risk of coronary heart disease. Efficacy is defined here as the magnitude of the effect produced by a given amount of drug, as demonstrated in placebo control trials; i.e., the effectiveness per unit dose. DATA SYNTHESIS: Treatment guidelines categorize patients by their risk of coronary events and set lower target cholesterol levels for patients at higher risk. Statins vary in their efficacy. If effectiveness is expressed as percent lowering in low-density lipoprotein cholesterol (LDL-C) and relatively little cholesterol lowering is required as in low-risk patients even statins of low efficacy provide adequate cholesterol lowering, and drug price is the determining factor of cost effectiveness. For patients at high risk the primary target group, which has been expanded in recent guidelines high-efficacy statins are required to meet the more ...