A Comparative Study of Adaptive Behavior and Intellectual Functioning in Children with Autism Spectrum Disorder, Attention Deficit Hyperactivity Disorder, and Typically Developing Children

Abstract

Background Autism Spectrum Disorder ASD known to include several differences in cognitive functions requires measurement of intellectual functioning along with adaptive behavior assessment.Objectives To understand the relationship between adaptive behavior scores and the findings of intellectual quotient IQ assessments in children with ASD to be able to use adaptive behavior scores for treatment and therapy plans in the absence of IQ scores.Method A cross-sectional comparative study was undertaken in a group of children with ASD N110 age 6 years to 12 years Attention Deficit Hyperactivity Disorder ADHD N31 and Typically Developing Children TDC N40 both groups aged between 7 years to 12 years. The diagnosis of ASD and ADHD was made by a consultant at the outpatient facility. The diagnosis was confirmed with the Social Communication Questionnaire SCQ and the Conners Rating Scale ndash Parent Short. The TDC group were recruited from the community. Adaptive behavior was assessed using the Vineland Adaptive Behavior Scale II VABS II. The Wechsler Intelligence Scale for Children-IV WISC-IV yielded a Full-scale IQ FSIQ and four index scores. The domain scores and the Adaptive Behaviour Composite ABC of the VABS II were analyzed with the FSIQ and index scores of the WISC-IVResults The obtained IQ scores were understood in association with adaptive scores. The scores were compared among three groups ndash ASD ADHD and TDC. There was a significant correlation between the VABS scores and the IQ scores for the entire sample. For the ASD group the Processing Speed Index PSI and Motor Skills MS domains did not share a relationship with the other domains. Similarly the Working Memory Index WMI and PSI indices did not have a significant correlation with the domains of the VABS. VABS and WISC-IV were poorly correlated for the TDC group.Conclusion The VABS and the IQ had a strong positive relationship in ASD. For children who were unable to complete a cognitive assessment and obtain an IQ score the VABS score could be the primary assessment to make treatment and therapy decisions and IQ assessment could be deferred until the child is more cooperative.nbsp