Predictive value of the index of desirable body weight for total body fat mass as measured by dilution of tritiated water--problems and limitations.
The index of desirable body weight is currently used for classification of patients' weights. We examined how it is related to the degree of adiposity, and whether it can serve in the prediction of body fat to the same degree as Quetelet's index. Sixty-five women and 142 men comprising a wide range of weight indices were studied. Body fat (F) was measured by the tritium dilution technique with a precision of +/- 1.26 kg. Regressions of F/W0 on the index of desirable weight W/W0 gave a correlation coefficient of 0.969 for women and 0.939 for men. Regressions of F/H2 on Quetelet's index W/H2 had correlation coefficients of the same order, i.e. 0.971 for women and 0.936 for men. Hence both indices are equally powerful for calculation of body fat within the study population. Further progress was achieved by multiple regression of F on W and W0 which yielded correlation coefficients of 0.976 for women and 0.953 for men. The residual standard deviation reflecting the mean difference between calculated and estimated fat was 3.4 kg for women and 3.8 kg for men. Despite this self-consistency, prediction of body fat for persons outside the study population is only possible within wide limits. These are given by about twice the residual standard deviation. Therefore, prediction of body fat from weight indices can only be used for detection of larger abnormalities in body composition.
Leonhardt
W
W
Clinic of Internal Medicine, Medical Academy Carl Gustav Carus, Dresden, GDR.
Hanefeld
M
M
Julius
U
U
Schulze
J
J
Fischer
S
S
Weck
M
M
Haller
H
H
D000328:Adult; D001823:Body Composition; D001835:Body Weight; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000175:diagnosis*; D012015:Reference Standards; D012044:Regression Analysis; D014316:Tritium
D014316:Tritium