BACKGROUND:

To be useful, a screening program depends on an acceptable, valid, and reliable test, and an efficacious and cost-effective intervention in the population of interest. Screening children to detect those at high risk of adult hypertension or hypercholesterolemia was examined from this viewpoint.

Long-term studies starting in childhood have so far revealed less than optimal validity of blood pressure and serum cholesterol levels in childhood as predictors of adult levels. However, information was sparse regarding reliability of measurements, accounting for which could improve validity. The efficacy of interventions that could be widely applied in childhood had not yet been demonstrated. In addition, the costs of an extensive screening program and risks such as misclassification, side effects, and labeling needed to be evaluated. The results of this study helped determine whether screening for risk factors in childhood was a useful method for preventing cardiovascular disease in adults.

DESIGN NARRATIVE:

The study examined the following factors that were key elements in the evaluation of screening: 1) within-person variability of BP and lipid measurements (i.e., the reliability of the test) and its impact on tracking of BP and lipids from childhood to adulthood, 2) calculation of predictive values, sensitivity, and specificity of childhood BP and lipid measurements considered as screening tests for adult values, after correcting for within-person variability (i.e., validity), 3) one potentially effective intervention for BP control in children, that is, calcium supplementation, and 4) evaluating the cost-effectiveness of screening to identify children at high risk of developing adult hypertension or hyperlipidemia.