Attention deficit disorder (ADD) with and without hyperactivity: Neuropsychological, academic, and psychosocial correlates of ADD subtypes in children.

The present study was designed to evaluate the external validity of Attention Deficit Disorder subtypes formed according to whether or not hyperactivity was present. The groups were compared on variables that reflected neuropsychological, academic, and psychosocial functioning. They were also compared on child and family history variables. Of particular interest was whether and to what extent the ADD subtypes could be distinguished on clinical neuropsychological measures that have been associated with executive or frontal lobe processes in adults. Sixty-two children with ADD+H and 22 children with ADD$-$H were selected from consecutive referrals to a hospital-based neuropsychology service. Few significant differences emerged when the groups were compared on neuropsychological, academic, and child and family history variables. It was found that the ADD$-$H group correctly identified fewer items on the Underlining Test, a result that was consistent with the notion that children with ADD$-$H encounter difficulties on certain tasks that stress complex visual search and perceptual-motor speed. However, overall, there was no compelling evidence to suggest that children with ADD+H have greater deficiencies on tasks that have traditionally been associated with executive processes as compared to children with ADD$-$H, or that learning disabilities are associated with one subtype more than the other. Significant group differences were found on behavioural and emotional adjustment variables that were not used in the classification of the children. The pattern of differences was largely consistent with the results of previous studies. In general, both groups exhibited more problems of an internalized nature (e.g., social withdrawal, unhappiness) as compared to normative data, although these problems were more common in the ADD$-$H group. Externalized problems (e.g., conduct disorders, aggression) were less common in the ADD$-$H group as compared to the ADD+H group, being almost non-existent within the school setting. Among the children with ADD+H, approximately 30% exhibited externalized problems at home and 50% exhibited such problems at school. The findings related to behavioural and emotional adjustment provide some support for the validity of subtyping children with ADD according to the presence or absence of hyperactivity. Source: Dissertation Abstracts International, Volume: 54-09, Section: B, page: 4910. Adviser: Byron Rourke. Thesis (Ph.D.)--University of Windsor (Canada), 1993