Meta-Analysis of Neuropsychological Measures of Executive Functioning in Children and Adolescents With High-Functioning Autism Spectrum Disorder

Existing literature on the profile of executive dysfunction in autism spectrum disorder showed inconsistent results. Age, comorbid attention-deficit/hyperactivity disorder (ADHD) and cognitive abilities appeared to play a role in confounding the picture. Previous meta-analyses have focused on a few components of executive functions. This metaanalysis attempted to delineate the profile of deficit in several components of executive functioning in children and adolescents with high-functioning autism spectrum disorder (HFASD). Ninety-eight English published case-control studies comparing children and adolescents with HFASD with typically developing controls using well-known neuropsychological measures to assess executive functions were included. Results showed that children and adolescents with HFASD were moderately impaired in verbal working memory (g=0.67), spatial working memory (g=0.58), flexibility (g=0.59), planning (g=0.62), and generativity (g=0.60) except for inhibition (g=0.41). Subgroup analysis showed that impairments were still significant for flexibility (g=0.57-0.61), generativity (g=0.52-0.68), and working memory (g=0.49-0.56) in a sample of autism spectrum disorder (ASD) subjects without comorbid ADHD or when the cognitive abilities of the ASD group and the control group were comparable. This meta-analysis confirmed the presence of executive dysfunction in children and adolescents with HFASD. These deficits are not solely accounted for by the effect of comorbid ADHD and the general cognitive abilities. Our results support the executive dysfunction hypothesis and contribute to the clinical understanding and possible development of interventions to alleviate these deficits in children and adolescents with HFASD. (C) 2016 International Society for Autism Research, Wiley Periodicals, Inc.