A Network Analysis of ADHD and ASD Symptoms in Chinese Children: Insights on Age and Gender Differences.

OBJECTIVE: This study aimed to explore the transdiagnostic interactions between ADHD and ASD symptoms in Chinese children, identifying core and bridging symptoms, and examining differences in symptom networks across gender and age subgroups. METHOD: Using data from a nationwide mental health survey of 71,217 Chinese children (mean age = 11.49, SD = 2.82), a symptom network analysis was conducted. ADHD and ASD symptoms were assessed via the Child Behavior Checklist (CBCL), with ASD items selected from an empirically derived CBCL autism scale. Network estimation was performed using the Glasso algorithm, and community detection was achieved through exploratory graph analysis (EGA). Network comparison tests (NCT) were used to evaluate differences in network structure and connectivity between gender (male vs. female) and age (younger vs. older) subgroups. RESULTS: Inattentive symptoms (I8 "Cannot concentrate," I78 "Inattentive/easily distracted") emerged as central bridging nodes linking ADHD and ASD symptoms. Three stable communities were identified: (1) an inattentive/internalizing cluster reflecting overlapping ADHD-inattentive and ASD features, (2) a hyperactive/impulsive and immature behavior cluster, and (3) a social withdrawal/low energy cluster representing core ASD features. Females exhibited significantly higher network connectivity than males (global strength: S = 1.05, p = 0.03), with tighter symptom interplay. Older children showed greater ADHD-ASD symptom overlap, though global strength differences were non-significant (S = 0.70, p = 0.13). CONCLUSION: Two inattentive symptoms (I8 and I78) emerged as among the most strongly connected items in the combined ADHD-ASD symptom profile, suggesting that attentional difficulties could play an important role in the psychopathological mechanisms underlying both conditions. Nevertheless, this cross-sectional finding does not establish causality; longitudinal and intervention studies remain necessary. Screening approaches tailored to gender differences and local cultural context could improve identification of these symptoms in Chinese children and adolescents. The present findings may also guide future refinements in school mental-health support and related policy development.