CROSS-VALIDATION OF THE SLAUGHTER SKINFOLD EQUATIONS FOR CHILDREN ANDADOLESCENTS

Prior to sexual maturation, children and adolescents have more water a nd less bone mineral content than adults, resulting in less dense fat- free body mass (FFM). This suggests that previously established adult skinfold/density equations are inappropriate for use with children and adolescents for the prediction of body fatness (%BF) and FFM. To over come this problem, Slaughter and colleagues have introduced new skinfo ld (SKF) equations that take into account the changing density of FFM in children and adolescents as they mature. The purpose of our study w as to cross-validate a select set of the Slaughter SKF equations by co mparing them with a criterion measurement (Lohman's Siri age-adjusted body density equation) in 122 subjects ranging in sexual maturation fr om pre- to post-pubescent and ranging in age from 8-17. Our cross-vali dation found very high intraclass (reliability) correlations (ICCs = 0 .98-0.99) and high validity correlations (rs = 0.79-0.99). The standar d errors of the estimate for %BF ranged from 3.5-4.6% and total errors for %BF ranged from 3.6-4.6%. The Slaughter equation using tricep and calf SKF for females was significantly different (P < 0.05) from the criterion measure in its prediction of %BF. In males, there was an int eraction between the SKF equation and subject maturation level. The da ta indicate that the Slaughter SKF equations hold promise for estimati ng body composition in children and adolescents but are still in need of refinement.