Patterns and Stability of Repetitive and Restricted Behaviors in Chinese Children With Autism: A 1–3 Year Follow‐Up Study

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by significant clinical heterogeneity. Sex‐based differences are observed in the core symptoms of ASD. This study investigated the patterns and stability of restricted and repetitive behaviors (RRBs) among Chinese children with ASD. For cross‐sectional comparisons, researchers recruited 1760 male and 350 female participants whose ages ranged from 4 to 17 years. The Social Responsiveness Scale‐2 (SRS‐2) was used to measure the core symptoms of ASD. Compared with males, females exhibited lower severity and incidence rates of RRB both overall and at the symptom level. Furthermore, multigroup confirmatory factor analyses demonstrated that sex‐related differences did not significantly affect the conceptualization of RRBs. An online follow‐up study involving a subset of participants (166 males and 41 females) revealed that RRB symptoms remained stable between the two visits for males; however, only specific symptoms were highly consistent over time for females. This study revealed potential sex‐related differences in RRBs among Chinese individuals with ASD and revealed sex‐dependent variations in symptom‐level presentation patterns and stability. These findings may contribute to a better understanding of the mechanisms underlying sex‐related differences and aid in the development of sex‐specific diagnostic criteria.