Performance of Children with Attention Deficit Hyperactivity Disorder and Anxiety/Depression on the WISC-III and Cognitive Assessment System (CAS)

Abstract

The purpose of this study was to examine differences in cognitive performance between samples of children diagnosed with ADHD, anxiety and/or depression, and the normative groups on two tests of ability. Matched samples of 25 children diagnosed with Attention Deficit Hyperactivity Disorder were contrasted with 25 children diagnosed with anxiety/depression. Both groups were also compared to the normative values for the Wechsler Intelligence Scale for Children, Third Edition (WISC-III) and tests of Planning, Attention, Simultaneous, and Successive cognitive processes from the Cognitive Assessment System (CAS). Children with ADHD had lower Planning scores than those with anxiety/depression (6.5 points; effect size of 0.6) and lower Planning scores than the standardization sample (12.7 points; effect size of 0.9). No significant difference was found between children with ADHD, children with anxiety and depression, and the matched clinical sample on the WISC-III. The findings are commensurate with other studies, suggesting that Wechsler scores differentiated the samples minimally but CAS scores appear sensitive to the cognitive processing difficulties experienced by children with ADHD.