Bioelectrical-impedence analysis as a measure of body composition in a West Indian population

ABSTRACT

Percent body fat (percent BF) was estimated in 50 males and 50 females aged 8-21 y by using hydrodensitometry (percent BF) and a bioelectrical-impedance analyzer (percent BF-BIA). The sample population was racially heterogenous, though predominantly of African origin. Percent body fat was computed from density by using an equation derived specifically for blacks. The BIA predicted percent BF with r2 = 0.77 (SEE = 3.7 percent BF), underestimating by a mean of 1.7 percent BF. Residuals ( percent BFd - percent BF-BIA) were normally distributed but were significantly correlated with age (P less than 0.01), although this effect was small. The theoretical bases for impedance analysis and for hydrodensitometry would appear for different reasons to impair applicability of these techniques to the present population and age group. However, for our population sample the BIA estimated percent BF as precisely as other simple techniques applied to other populations. (AU)