Body Mass Index, Waist Circumference and Waist-to-Hip-Ratio in the Prediction of Obesity in Turkish Teenagers
The aim of this study was to identify the usefulness of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) in screening for obesity in teenagers by using the receiver operating characteristic (ROC). To select the sample set in this cross-sectional study, a stratified random sampling approach was utilized. Weight, height, WC, hip circumference and body fat percentage (BFP) were measured in 1118 children of both genders (597 boys and 521 girls), aged from 10 to 15 years old. Percentiles of BMI and Centers for Disease Control and Prevention-United States (CDC-US)-growth chart for boys and girls aged from 10 to 15 years old were presented. ROC analyses were then used to evaluate the performances of three anthropometric indices; BMI, WC and WHR had strong positive correlations with BFP (r=0.49-0.77) in both girls and boys within indicated age group. The area under the curves (AUCs) were high in both girls and boys for BMI, 0.795 and 0.893, respectively, and WC, 0.767 and 0.853, respectively, and were a little lower, 0.747 and 0.783, respectively, for WHR. In conclusion, this study demonstrates that the prevalence of being overweight and obese among teenagers of both sexes in our data set does not differ from CDC-US-growth chart. In addition, BMI and WC are two important predictors for teenagers to become overweight and obese, while WHR is less useful for this purpose.