Screening in health fairs. A critical review of benefits, risks, and costs.

Health fairs provide multiphasic screening to more than 2 million Americans each year, and the number is growing rapidly. Nearly 40 different tests are in use, commonly including the measurement of up to 30 different blood chemistry levels. This report reviews the activities in a sample of 940 health fair sites and examines the experience regarding six specific screening procedures (blood pressure, anemia, blood chemistries, glaucoma, hearing, and fecal occult blood testing). Widespread use of these and other tests raises complex issues of cost, risk, and benefit. Rates of false alarm of healthy people and false reassurance of those at risk may be high for some tests, and the benefits of detecting new disease are easily overestimated. Detailed data collection and evaluation could help health fair sponsors to identify more rational screening strategies.