Our clinically applicable method assigns a child's or adolescent's BMI value to a group with a known probability of overweight or obesity in adulthood.

Stature is an important variable in several indices of nutritional status that are applicable to elderly persons. However, stature is difficult or impossible to measure in the nonambulatory elderly person, or its value may be spurious if measured in those elderly persons with excessive spinal curvature. Simple equations are presented for estimating the stature of elderly men from a recumbent measure of knee height and for elderly women from a recumbent measure of knee height and age. The 90 per cent error bounds for these equations for an individual are about plus or minus 6.0 cm. Knee height is highly correlated with stature.

Background: Previous studies to develop and validate bioelectrical impedance analysis (BIA) equations to predict body composition were limited by small sample sizes, sex specificity, and reliance on reference methods that use a 2-component model. Objective: This study was designed to develop sex-specific BIA equations to predict total body water (TBW) and fat-free mass (FFM) with the use of a multicomponent model for children and adults. Design: Data from 5 centers were pooled to create a sample of 1474 whites and 355 blacks aged 12-94 y. TBW was measured by dilution, and FFM was estimated with a multicomponent model based on densitometry, isotope dilution, and dual-energy X-ray absorptiometry. Results: The final race-combined TBW prediction equations included stature 2 /resistance and body weight (R 2 = 0.84 and 0.79 and root mean square errors of 3.8 and 2.6 L for males and females, respectively; CV: 8%) and tended to underpredict TBW in black males (2.0 L) and females (1.4 L) and to overpredict TBW in white males (0.5 L) and females (0.3 L). The race-combined FFM prediction equations contained the same independent variables (R 2 = 0.90 and 0.83 and root mean square errors of 3.9 and 2.9 kg for males and females, respectively; CV: Ϸ6%) and tended to underpredict FFM in black males (2.1 kg) and females (1.6 kg) and to overpredict FFM in white males (0.4 kg) and females (0.3 kg). Conclusion: These equations have excellent precision and are recommended for use in epidemiologic studies to describe normal levels of body composition.