Application of weight-height ratios and body indices to juvenile populations--the National Health Examination Survey Data.

Abstract-Properties of four weight-height ratios were studed in data from the U.S. Health Examination Survey (Cycles 11 and III) of a national probability sample of youths aged 6-I 7 yr (N = 13.867). These ratios (weight/height, weight/height’. weight/height3, weight/body surface area) were examined for their correlation with adiposity (infrascapular skinfold thickness) and muscle mass (estimated muscle circumference) and for their relationship to selected physiologic and biochemical measurements. Weight/height’ (Quetelet’s index) correlates best with skinfold thickness for all age-race-sex groups. However, weight-height ratios may be a better indicator of muscle mass than of adiposity because the ratios generally show higher correlations with muscle circumference than with skinfold thickness. Weight/body surface area (BSA index) is the ratio which shows the highest overall correlation with muscle circumference. The relationships of the ratios are different for various biochemical and physiologic parameters, and these data can be used for selection of an index appropriate to the investigative aims of the study.