The validity of estimating heart disease reduction from a Framingham logistic equation.
We compared two ways in which a logistic equation could be used to estimate the number of heart disease events prevented after lowering blood cholesterol levels. Men were selected from an Australian population survey who met the entry criteria of the Lipid Research Clinics Coronary Primary Prevention Trial (LRC-CPPT). The numbers of heart disease events expected over 7.4 years were calculated from the logistic equation after reducing the men's blood cholesterol by the amounts achieved in the LRC-CPPT placebo and treatment groups (our simulated placebo and treatment groups). The number of events prevented was calculated as the absolute difference between the simulated groups (9.48 per 1000 men per 7.4 years) and the percentage difference of the simulated groups multiplied by the observed incidence rate in the LRC-CPPT placebo group (13.66 per 1000 men per 7.4 years). The second estimate was closer to that observed in the LRC-CPPT (17.10 per 1000 men per 7.4 years), and we recommend this approach in cost-effectiveness studies.
Kinlay
S
S
Centre for Clinical Epidemiology and Biostatistics, Faculty of Medicine, University of Newcastle, NSW, Australia.
O'Connell
D
D
Evans
D
D
Francis
L
L
D001315:Australia; D001794:Blood Pressure; D002784:Cholesterol / Q000097:blood; D003327:Coronary Disease / Q000453:epidemiology / Q000517:prevention & control*; D003362:Cost-Benefit Analysis; D004812:Epidemiologic Methods; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D011322:Primary Prevention; D012307:Risk Factors; D012907:Smoking
D008055:Lipids; D002784:Cholesterol