Peer Interaction in Late-Diagnosed Autistic Adolescent Boys and Girls.

Background: This study examined peer interactions among late-diagnosed autistic adolescents, focusing on biological sex differences. Methods: Participants included 61 adolescents aged 12-18 years (31 boys, 30 girls) with an Intelligence Quotient (IQ) > 75, all diagnosed within the past three years. Peer interactions were assessed using the APIOS-A, an adapted version of the preschool observational tool (APIOS). Parents reported on autistic traits via the Social Responsiveness Scale (SRS-2), which measures social communication difficulties; socialization skills through the Adaptive Behavior Assessment System (ABAS-II), which assesses adaptive functioning; and behavioral problems using the Child Behavior Checklist (CBCL), which identifies emotional and behavioral issues. These measures were utilized to compare social profiles across sexes. Results: The APIOS-A demonstrated good reliability for identifying socio-communicative difficulties in both boys and girls. Findings indicated that boys and girls showed similar peer interaction challenges, with subtle differences in conversational reciprocity, cognitive flexibility, and humor use. Associations between behavioral characteristics and peer patterns varied by sex, highlighting the importance of tailored approaches. Conclusions: These results underscore the need for sex-sensitive assessment tools and tailored interventions for late-diagnosed autistic adolescents. Integrating observational and parental measures may enhance understanding and support their social development.