Abstract
In order to evaluate the variable and constant error of skinfold prediction equations for estimating body density and body fat, 18 skinfold and girth measures were determined in 40 young males. The subjects were also weighed underwater to determine the criterion body density directly. The constant errors of prediction were very high, ranging from −10 to 122 percent. Validity coefficients ranged from r = .795 to .863; thus the predictive error of individual scores was 25 to 37 percent. In view of the large constant errors, the utility of these formulas for clinical application in estimating leanness and fatness is questionable. The relative ordering of individuals on the leanness-fatness scale can be accomplished more successfully, but the validity is moderate rather than high.