Reference data for obesity: 85th and 95th percentiles of body mass index (wt/ht2) and triceps skinfold thickness.

Body mass index (BMI) and triceps skinfold thickness (TSF) are commonly used measures of adiposity in clinical and epidemiologic studies. The 85th and 95th percentiles of BMI and TSF are often used operationally to define obesity and superobesity, respectively. Race-specific and population-based 85th and 95th percentiles of BMI and TSF for people aged 6-74 y were generated from anthropometric data gathered in the National Health and Nutrition Examination Survey 1 (NHANES I). The complex sample design of the survey is reflected in the reference values presented. Racial differences in these extremes of the distribution do not emerge until adulthood. Researchers may choose population-based, race-specific, or age-specific criteria for obesity on the basis of assumptions underlying their specific research questions.