Validity of anthropometric techniques for estimating percentage body fat in obese females before and after sizable weight loss.

Abstract

AbstractThe validity of selected generalized (n = 7) and obese population‐specific (n = 2) skinfold and girth based anthropometric equations (using hydrostatic weighing as the criterion measure) was evaluated in 19 obese women before and after a mean body weight loss of 19.4 kg (percent body fat was reduced from 45.3% to 35.4%). For the present study, evaluation criteria of mean differences in percent body fat (%BF) of < 3%, r values > 0.70, and total error (T.E.) values of < 5% were selected. Only the equations that utilized girths as part of the prediction technique (Barrows and Snook, 1987; Jackson et al., 1980; Tran and Weltman, 1989; Weltman et al., 1988) resulted in mean differences in %BF of less than 3%, r values of > 0.70 and T.E. values of less than 5% in obese women before weight loss. After 19.4 kg of weight loss, all but three of the equations resulted in mean differences in %BF of less than 3%, r values of > 0.70 and T.E. values of less than 5%. The obese population‐specific equations of Barrows and Snook (1987) and Weltman et al. (1988) were not accurate predictors of body composition after weight loss as they resulted in mean differences of 4.5–7.0 %BF. Although some of the equations examined were valid predictors of %BF either before or after weight loss, only the Jackson et al. (1980) equations which utilized both skinfolds and hip girth, and the Tran and Weltman (1988) equation which utilized trunk girths, resulted in mean differences of < 3 %BF, r values > r = 0.70, and T.E. scores of < ± 5 %BF both before and after weight loss. It was concluded that the prediction techniques of Jackson et al. (1980) and Tran and Weltman (1989), which utilize girth measures as part of the prediction technique, may have clinical utility for estimating changes in %BF in obese females before and after sizable weight loss. © 1993 Wiley‐Liss, Inc.