Differences in autism features and adaptive functioning between adolescents with autism spectrum disorder and social...

This study aimed to characterize adolescents with social communication disorder (SCD) in comparison with those with autism spectrum disorder (ASD) across two dimensions: autism features and adaptive functioning. SCD shares social communication difficulties with ASD, resulting in unclear diagnostic boundaries and raising concerns about its clinical utility given that existing research and resources remain largely ASD-oriented.

Data from 76 adolescents with ASD and 44 with SCD (ages 10-18 years) were analyzed. Lifetime and current autism features were assessed using the Autism Diagnostic Interview-Revised (ADI-R) and Social Responsiveness Scale, Second Edition (SRS-2), respectively, and adaptive functioning using the Vineland Adaptive Behavior Scales, Second Edition. Propensity score matching was performed using age and Full-Scale Intelligence Quotient, and group differences were compared before and after matching. Exploratory interaction analyses additionally examined potential moderators of group differences.

After matching, adolescents with SCD showed less severe lifetime autism features across the core ADI-R domains, with large effect sizes (ds = .98-1.34, all p <.001). Current autism features showed smaller group differences, which remained significant across all SRS-2 subscales except Social Motivation (ds = .46-.68, p = .004-.046). Adolescents with SCD showed better adaptive functioning than those with ASD, although group differences in Communication (p = .085) and Socialization (p = .144) were no longer statistically significant after matching. Psychiatric comorbidity moderated group differences in Communication, Socialization, and overall adaptive functioning, while attention-deficit/hyperactivity disorder showed a similar but less robust pattern for Communication, which did not remain significant after correction.

Overall, accounting for age and intellectual ability, the distinction between ASD and SCD remained evident at the symptom level, whereas functional differences were partly influenced by these factors. These findings suggest that diagnostic classification alone may not fully capture the functional needs of adolescents with ASD and SCD, highlighting the importance of a multidimensional approach that considers symptom profiles, adaptive functioning, developmental and intellectual factors, and psychiatric comorbidity.