| The cognitive profile of a sample of 118 children (ages 7-17) with Attention Deficit/Hyperactivity Disorders (ADHD) was compared to a sample of 62 non-ADHD clinically referred children using the Stanford-Binet Fifth Edition. This was an archival study utilizing a sample of children referred to the Education Clinic at the University of Alberta between the years 2003 and 2007. Classification of ADHD subjects and control was based upon multiple sources of evidence, including the scores from the Behavior Assessment System for Children (first or second editions) or the Conners' Rating Scales-Revised, as well as other clinically relevant information. The ADHD sample was broken into four groups, all ADHD individuals together (ADHD-collapsed; n=118) and the three subtypes; ADHD-combined (n=46), ADHD-inattentive (n=61), and ADHD-hyperactive (n=11). Analysis was completed for between-group and intra-individual difference levels. This included MANOVA of the five factor scores, as well as verbal and non-verbal Working Memory (WM) and Quantitative Reasoning subtests. Intra-individual difference analysis used ANOVA and chi-square of factors and subtests of interest. Intra-individual difference analysis examined the relative weakness of a particular score within an individual's overall profile. Of all five factors, WM was the only factor that showed significant differences across all the analysis. Significant findings for Verbal Quantitative Reasoning (VQR) occurred in the ADHD-inattentive group, differentiating it from the other subtypes in all analysis. Correcting for the number of comorbid conditions resulted in more significant findings at the subtest level. Results from the study also suggest the utility of differentiating subjects based upon severity of ADHD symptoms. Future research comparing the subtypes to each other directly, based upon symptom severity, would be of interest. |
