Comparative performance of multiple novel obesity indices for MAFLD screening in Chinese children: the body roundness index as a practical predictor

In recent years, as childhood obesity rates soar globally, there has been a concomitant increase in the prevalence of metabolic dysfunction-associated fatty liver disease (MAFLD). The intent of this analysis is to explore the correlation between four novel obesity indices and pediatric MAFLD, and to compare their varying screening performance for MAFLD. We used data from the Wuxi (China) Children’s Nutrition and Health cohort. Logistic regression and restricted cubic spline (RCS) were employed to assess the associations between the obesity indices, including visceral adiposity index (VAI), lipid accumulation product (LAP), body roundness index (BRI), and weight-adjusted waist index (WWI) with MAFLD in children. Furthermore, Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive performance of the four novel obesity indices, and DeLong’s test was applied to compare the AUC of the best-performing index (BRI) with those of traditional anthropometric measures (BMI, WC, and WHtR). A total of 1,214 children (aged 6–14 years) were enrolled in this study, with a mean age of 10.3 years and a boy proportion of 56.4%. Among them, 205 (16.8%) were diagnosed with MAFLD, while the remaining 1,009 (83.1%) served as controls. The multivariate logistic regression revealed that the VAI, LAP, BRI and WWI displayed a marked association with MAFLD in children (all p < 0.001). Among them, BRI exhibited high and consistent screening performance for pediatric MAFLD across all analyzed subgroups. For instance, in the subgroup with CAP ≥ 248 dB/m, it achieved an AUC of 0.929 (95% CI: 0.913–0.945), comparable to traditional BMI and WHtR, and significantly outperformed WC. Our findings demonstrated four the novel obesity indices are significantly associated with MAFLD in children. The BRI emerges as a simple, reliable, and clinically useful screening tool that captures visceral fat distribution and may aid in early risk stratification.