The study added to the CHD Policy Model the capability to model the consequences of reductions in LDL cholesterol and increases in HDL/LDL ratios in the United States population. The CHD Policy Model was used for several studies, including: to compare the implications of using alternative epidemiologic studies as the basis for estimating the association between cholesterol levels and CHD risk; to derive cutting points for initiating cholesterol reduction, specific to age, sex, and CHD risk factors, and based on cost-effectiveness criteria; to compare the cost-effectiveness of specific targeted and population-wide strategies for cholesterol reduction; to incorporate the effects of treatments on quality of life, including both adverse effects of cholesterol-lowering drugs and reductions in CHD morbid events; and finally, to perform a cost-effectiveness analysis of cholesterol screening, incorporating costs of screening, effects of measurement error on misclassification of patients, and variations in individual cholesterol levels over time.