PREDICTION OF BODY-COMPOSITION IN PREMENOPAUSAL FEMALES FROM DUAL-ENERGY X-RAY ABSORPTIOMETRY

Four methods for predicting body composition were comp red in premenop ausal females (n = 100), 28-39 yr old, by using underwater weighing (U WW) as the criterion method. The four methods were dual energy X-ray a bsorptiometry (DEXA), skinfolds, bioelectrical impedance, and body mas s index. The sample had a mean percent fat (%fat) of 29.7 +/- 6.8% (SD ) by DEXA and 29.9 +/- 6.8% measured by UWW. DEXA yielded a standard e rror of estimate (SE) of 2.4% (r = 0.91) for the prediction of %fat fr om UWW. When %fat was estimated from other methods, larger SEs were ob tained: 3.0% for skinfolds, 3.3% for body mass index, and 2.9% for bio electrical impedance (height/resistance) plus weight. Individual body density values derived from UWW were corrected for bone mineral variat ion. DEXA predicted the corrected body density with a lower SE (0.0040 vs. 0.0053 g/ml) than the original density values. We conclude that D EXA was a precise method and correlated highly with fat-free body weig ht and %fat from UWW in this homogeneous female sample.