Low Diagnostic Accuracy of Body Mass Index-Based and Waist Circumference-Based References of Childhood Overweight and Obesity in Identifying Overfat among Chinese Children and Adolescents

This study aimed to investigate the diagnostic accuracy of body mass index- (BMI-) based and waist circumference- (WC-) based references for childhood overweight and obesity in screening overfat individuals among 2134 Chinese children and adolescents. In this study, overfat status was defined as over 25% body fat for boys and over 30% for girls. Childhood obesity or overweight was defined by four BMI-based references and two WC-based references. All BMI-based references for obesity showed low sensitivity (SE) (0.128-0.473) but high specificity (SP) (0.971-0.998) in detecting overfat individuals in the current population. SE values increased from 0.493 to 0.881 when BMI- and WC-based references for overweight were used to detect overfat individuals. All references for overweight showed high SP rates (0.816-0.966). To improve diagnostic accuracy for childhood obesity, further studies may define a cut-off value for childhood obesity specific for a local population and ethnicity by using health-related overfat data.