NEW AGE-ADJUSTED MEASURE OF BODY-FAT DISTRIBUTION IN CHILDREN AND ADOLESCENTS - STANDARDIZATION OF WAIST-HIP RATIO USING MULTIVARIATE-ANALYSIS

OBJECTIVES: To explore a new anthropometric index of body fat distribu tion adjusted for ages ranging from 6-15 y in both boys and girls. DES IGN: Sex, age, and 11 anthropometric variables were subjected to princ iples component analysis. Based on these results, we developed a new a nthropometric index, namely an are-adjusted measure of body fat distri bution. This index was evaluated statistically for suitability of use in epidemiological surveys. SUBJECTS: Japanese children, including obe se and nonobese subjects, in one elementary amid one junior high schoo l in Yamanashi Prefecture, Japan: 508 boys and 549 girls whose ages ra nged from 6 y 1 mon-15 y. MEASUREMENTS: Measurements included the heig ht (Ht), body weight, circumference of the waist, hip and thigh. Body mass index, the ratios of the waist hip or thigh to the Ht, waist-hip ratio (WHR) and waist-thigh ratio were calculated.RESULTS: The first p rincipal component (PC 1) accounted for 49.8% of the total variation, and was interpreted as an indicator of the general size of an individu al. PC 2 accounted for 25.9%, and was interpreted as a shape measure t hat indicates body fat distribution. Calculation of WHR/Ht a parameter that represented PC 2 adjusted by PC 1, gave an highly robust linear regression equation for age by gender, The residuals from the regressi on line for WHR/Ht deviated from normal distribution only in the boys, whereas the mean residual was nearly zero and distribution of the res iduals was similar in three age subgroups by gender, supporting the us e of the common standard deviation score in all age groups as an indic ator of body fat distribution. CONCLUSION: The common standard deviati on score of WHR/Ht can serve as an epidemiological index of body fat d istribution adjusted for ages between 6 and 15 y.