Objective: To compare the most commonly used equations to predict body fatness from skinfold thickness, in male and female adolescents, with dual-energy X-ray absorptiometry (DXA) as a reference method of fatness measurement. Design: Cross-sectional nutrition survey. Setting: General adolescent population from Zaragoza (Spain). Subjects and methods: A total of 238 Caucasian adolescents (167 females and 113 males), aged 13.0-17.9 y, were recruited from 15 school groups in 11 public and private schools. The percentage fat mass (%FM) was calculated by using skinfoldthickness equations. Predicted %FM was compared with the reference %FM values, measured by DXA. The lack of agreement between methods was assessed by calculating the bias and its 95% limits of agreement.Results: Most equations did not demonstrate good agreement compared with DXA. However, in male adolescents, Slaughter et al equations showed relative biases that were not dependent on body fatness and the limits of agreement were narrower than those obtained from the rest of equations. In females, Brook's equation showed nonsignificant differences against DXA and the narrowest 95% limits of agreement. Only biases from Brook and Slaughter et al equations were not dependent on body fatness in female adolescents. Conclusions: Accuracy of most of the skinfold-thickness equations for assessment of %FM in adolescents was poor at the individual level. Nevertheless, to predict %FM when a relative index of fatness is required in field or clinical studies, Slaughter et al equations may be used in adolescents from both sexes and the Brook equation in female adolescents. Sponsorship: Instituto de Salud Carlos III, Spain.

Waist circumference seems to be the best predictor of children with the metabolic syndrome in paediatric clinical settings.

Objective: To present body fat patterning reference standards to identify children with a predominant distribution of body fat in the abdominal or truncal region of the body. Design: Cross-sectional study in a representative sample of Spanish adolescents aged 13-18 years. Subjects: A total of 2160 adolescents with a complete set of anthropometric measurements (1109 males and 1051 females). Measurements: Weight, height, body mass index, skinfold thickness (biceps, triceps, subscapular, suprailiac, thigh, calf) and waist and hip circumferences. Results: In the majority of the age groups, subscapular/triceps skinfolds ratio, trunk-to-total skinfolds percent (TTS%)and waist circumference values were significantly higher in males than in females; hip circumference was higher in females than in males, except at 15.5 years. In males, age showed a significant effect for all the body fat distribution indices; however, in females, the effect was only significant for triceps skinfold, waist and hip circumferences and waist-to-hip ratio. Smoothed age-and sexspecific triceps skinfold, subscapular skinfold, subscapular/triceps skinfolds ratio, TTS%, waist circumference and hip circumference, waist-to-hip and waist-to-height ratio percentile values for male and female adolescents have been established. Conclusion: These reference data for waist circumference and the other fat patterning indices, together with data from other countries, will help to establish international central obesity criteria for adolescents. The presented percentile values will give the possibility to estimate the proportion of adolescents with high or low regional adiposity amounts.

Aim: To identify the best anthropometric predictor of the metabolic syndrome in children. Methods: Screening performance was evaluated in a clinical setting. The study included 140 children: 72 non‐obese and 68 with non‐syndromal obesity. Body mass index (BMI), waist circumference and triceps/subscapular skinfolds ratio were used as predictor variables, and systolic blood pressure, diastolic blood pressure, glucose, uric acid, fasting insulin, triglycerides and HDL‐C as metabolic syndrome variables. Results: The areas under the receiver operating characteristic (ROC) curves were 0.849 (95% CI: 0.780,0.919) for BMI, 0.868 (95% CI: 0.801,0.934) for waist circumference and 0.834 (95% CI: 0.757,0.910) for the triceps/subscapular skinfolds ratio. No statistically significant differences were found for the three areas under the ROC curves. The point on the ROC curve closest to 1 corresponded to the 65th percentile for BMI, to the 70th percentile for waist, and to the 40th percentile for the triceps/subscapular skinfolds ratio. Conclusion: Waist circumference seems to be the best predictor of children with the metabolic syndrome in paediatric clinical settings.

Objective: To develop equations, from some simple anthropometric measurements, for the prediction of body density from underwater weighing in male spanish children and adolescents. Subjects: One hundred and seventy-®ve males, aged 7.0±16.9 y, participated in this study, they were recruited from primary and secondary schools. Measurements: Body weight and height and skinfold thicknesses by anthropometry, body density by underwater weighing. Results: Correlations between body density and body mass index (BMI) were high until 14.0±16.9 y. Correlations between body density and log S 4 skinfolds were higher than those with BMI at all ages. Log S 4 skinfolds explained between 61% (14.0±16.9 y) and 68% (11.0±13.9 y) of the body density variance. Regression equations for body density from BMI and triceps skinfold thickness explained between 51% (14.0±16.9 y) and 68% (7.0±10.9 y) of the body density variance. Conclusions: The best estimators of body density in the children and adolescents studied were log S 4 skinfolds and a combination of BMI and triceps skinfold.