Measurement error and reliability in four pediatric cross-sectional surveys of cardiovascular disease risk factor variables--the Bogalusa Heart Study.

Four cross-sectional epidemiologic studies of children 5-17 years of age were conducted between 1973 and 1982 in the community of Bogalusa, La. Anthropometric, blood pressure and serum lipid variables were measured. Measurement error (precision) and reliability (reproducibility) were estimated for these risk factor variables of coronary artery disease. Precision was less than 0.8 cm for height, 0.8 kg for weight, and 1 mm for triceps and subscapular skinfold over the four surveys. Measurement error for the mercury sphygmomanometer and automatic blood pressure instruments was between 4 and 5 mmHg during this same period. Except for triglycerides and total and alpha-lipoprotein cholesterols that stabilized at lower levels after the first survey, precision of laboratory variables remained nearly constant over the 9 years of survey. Anthropometric measurements were found to be the most reliable followed next by the laboratory and then blood pressure measurements. These estimates offer guidelines applicable to data collection and processing in future investigations of risk factor variables for coronary artery disease.