The Third National Health and Nutrition Examination Survey, 1988-1994 (NHANES III) is a cross-sectional sample of the civilian, noninstitutuionalized US population. The purpose of the allergy portion of the survey is to obtain information on the prevalence of allergic disease and allergen skin test reactivity in the US population. Currently the NHANES II survey, 1988-1991, is being analyzed to determine the prevalence of immediate cutaneous hypersensitivity to FDA standardized (dustmite, cate, ryegrass, short ragweed, russian thistle) and unstandardized (White oak, Bermuda grass, German cockroach, Alternaria, peanut) allergenic extracts in the US population. The influence of sociodemographic factors, race, ethnicity on the prevalence estimates of hypersensitivity and respiratory symptoms will be analyzed.