The Behavioral Risk Factor Survey and the Stanford Five-City Project Survey: A comparison of cardiovascular risk behavior estimates

Background. Nearly all state health departments collect Behavioral Risk Factor Survey (BRFS) data, and many report using these data in public health planning. Although the BRFS is widely used, little is known about its measurement properties. This study compares the cardiovascular risk behavior estimates of the BRFS with estimates derived from the physiological and interview data of the Stanford Five-City Project Survey (FCPS). Method. The BRFS is a random telephone sample of 1588 adults aged 25 to 64; the FCPS is a random household sample of 1512 adults aged 25 to 64. Both samples were drawn from the same four California communities. Results. The surveys produced comparable estimates for measures of current smoking, number of cigarettes smoked per day, rate of ever being told one has high blood pressure, rate of prescription of blood pressure medications, compliance in taking medications, and mean total cholesterol. Significant differences were found for mean body mass index, rates of obesity, and, in particular, rate of controlled hypertension. Conclusions. These differences indicate that, for some risk variables, the BRFS has limited utility in assessing public health needs and setting public health objectives. A formal validation study is needed to test all the risk behavior estimates measured by this widely used instrument.