Comparability of Criteria and Methods in the Epidemiology of Cardiovascular Disease

T HE high morbidity and mortality from atherosclerotic and hypertensive cardiovascular diseases in the United States emphasize the need for their prevention and control and have led to epidemiologic research in these areas in this and other countries. In the application of epidemiologic principles to the study of atherosclerosis and high blood pressure, various criteria, methods and technics are employed in collecting, classifying, analyzing, and interpreting the data. Differences in criteria and methods among studies make it difficult or impossible to compare or combine their findings. While investigators must have the freedom to choose their own research procedures, full use of the data can be made only if some minimal standards for mutually agreeable methods and criteria are set and followed. Burgess, Fejfar, and