BACKGROUND: Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders that affect children's social interaction and communication skills and exert a serious effect on children's perception, language, emotion, and especially social interaction development. AIM: To determine the clinical and psychological characteristics of children with ASD according to the C-PEP-3. METHODS: This retrospective study included 225 children with autism aged 2-7 years who were treated in our hospital from 2021 to 2024. The C-PEP-3 scale was used for assessment, and the evaluation results were analyzed. RESULTS: The comparison of children with ASD in the age groups of <
3.5 years and >
3.5 years revealed significant differences in the scores of imitation, fine motor, gross motor, hand-eye coordination, cognitive performance, and verbal cognition development areas (P: Pass) ( CONCLUSION: The C-PEP-3 scale reflects the differences in clinical characteristics of children with autism, and the pathological scale is associated with the severity of developmental function areas. The C-PEP-3 scale can be utilized to assess the effect of age changes on children with autism. Attention in rehabilitation should be focused on addressing the pathological behaviors of children with autism.