Skeletal Maturity‐Adjusted Body Mass Index for Age Percentile Charts for Chinese Children and Adolescents

AIM: Body mass index (BMI) for age charts may bias overweight or obesity assessment in children with advanced or delayed maturation. This study developed skeletal maturity-adjusted BMI for age percentile charts. METHODS: This secondary analysis included 15 598 children aged 3 to 19 years from a cross-sectional study. Skeletal maturity was assessed using the radius stage based on the Tanner-Whitehouse 3 scoring method. The association between BMI and radius stage, as well as between chronological age and BMI within each radius stage, was examined. Percentile curves for skeletal maturity-adjusted BMI for age were constructed using the Box-Cox power exponential distribution model. RESULTS: A significant association was found between BMI and radius stage. Within most radius stage categories, chronological age was significantly correlated with BMI. The influence of skeletal maturity on BMI was illustrated by overlaying the skeletal maturity-adjusted BMI percentile curves onto the conventional BMI for age growth charts. CONCLUSION: The skeletal maturity-adjusted BMI for age chart serves as a valuable tool for assessing BMI in children and adolescents with advanced or delayed skeletal maturation.