Skinfold thickness measurements in obese subjects.

To determine the accuracy of skinfold thickness measurements in body composition assessment, skinfold thicknesses, bioelectrical impedance, body density by underwater weighing, and total body water by deuterium dilution were determined in 105 healthy adults who varied widely in body fatness. Body fat ranged from 2.9% to 61.2% of body weight and a substantial number of obese subjects was included. The correlation between body fat calculated from skinfold equations and body fat measured by underwater weighing was in the same range as that between body fat estimated from impedance and underwater weighing. However, body fat calculated both from skinfold equations and bioelectrical impedance tended to be underestimated compared with body fat calculated from underwater weighing and total body water in the most obese subjects. In obese subjects it was not possible to measure significant numbers of skinfold thicknesses because of the inadequate size of the calipers.