[The performance of children with AD(H)D according to the HAWIK-IV]

The focus of the present study were performances of N = 433 children and adolescents with AD(H)D on the German version of the Wechsler Intelligence Scale for children (HAWIK-IV). Furthermore, we investigated whether test results depend on comorbid disorders based on subgroups (n = 212, n = 262, n = 217) composed by excluding individuals based on comorbidities on either (a) the first, (b) the second, and (c) the first and the second axis of the multiaxial classification scheme for mental disorders in childhood and adolescents. The specificity of the AD(H)D profile was investigated by comparing it against a clinical control group of children with anxiety or other emotional disorders (N = 41). As expected, a significant deficit in the Speed Index was shown not only in the total sample of all AD(H)D children, but also in the subsample cleared of comorbidities. There was also a deficit in Working Memory, although this result was no longer found in the subsample of AD(H)D children without comorbidities. The profile of the AD(H)D-only group was not significantly different from the profile of the clinical control group. The results support the assumption that AD(H)D is associated with deficits in Processing Speed. Working Memory deficits seem to occur only if comorbid disorders are present.