Intelligence levels and autistic severity are important contributors of adaptive functioning and cognitive-adaptive functioning gaps in school-aged children with ASD

Background Children with autism spectrum disorder (ASD) frequently presented weaker adaptive functioning compared with typically developing children. Multiple affecting factors of adaptive functioning in ASD individuals had been explored in previous studies. Methods Data of age, gender, parental education, place of residence, behavioral intervention, attention deficit hyperactivity disorder comorbidity, Wechsler Intelligence Scale for Children (WISC) scores and Autism Diagnostic Observation Schedule (ADOS) scores were collected in 107 school-aged children with ASD. Adaptive functioning of ASD subjects were evaluated through Adaptive Behavior Assessment System (ABAS). Spearman correlation analyses were applied to investigate the associations between intelligence quotient (IQ) scores, ASD related symptoms and adaptive functioning and cognitive-adaptive functioning gaps. Hierarchical regressions were performed in sequence to examine the effects of gender, age, parental education, intelligence, autistic severity and behavioral factors on General Adaptive Composite (GAC) in children with ASD. Results Verbal Comprehension Index (VCI), Perceptual Reasoning Index (PRI), Working Memory Index (WMI) and Processing Speed Index (PSI) of WISC were positively correlated with Conceptual domain, Social domain and GAC ( P  < 0.01). There were positive correlations between VCI, PRI and PSI and Practical domain ( P  < 0.01). Positive associations were discovered between full-scale IQ (FSIQ) and the three domains and GAC in ABAS ( P  < 0.01). Social Affect (SA), Restricted and Repetitive Behavior (RRB) and Total scores of ADOS were negatively correlated with Conceptual, Social and Practical domains ( P  < 0.05). Comparison Scores were negatively correlated with Conceptual domain and Social domain ( P  < 0.05). Negative correlations were found between SA, RRB, Total scores, Comparison Scores and GAC ( P  < 0.05). VCI, PRI, WMI, PSI and FSIQ were positively correlated with FSIQ-Conceptual, FSIQ-Social, FSIQ-Practical and FSIQ-GAC gaps ( P  < 0.01). SA was inversely correlated with FSIQ-Conceptual and FSIQ-Practical gaps ( P  < 0.05). Total scores were inversely correlated with FSIQ-Conceptual, FSIQ-Practical and FSIQ-GAC gaps ( P  < 0.05). FSIQ was positively correlated with GAC in the total model (β= 0.25, P  = 0.015). There were significant inverse associations between RRB and GAC in the total model (β=−0.28, P  = 0.014). Conclusions Intelligence levels and autistic severity were important contributors of adaptive functioning in school-aged children with ASD. IQ and ASD symptoms were also crucial factors affecting the cognitive-adaptive functioning gaps in ASD.