A preliminary validation of subtypes of DSM-IV Attention-Deficit/Hyperactivity Disorder

Preliminary validity of DSM-IV ADHD was examined in a sample of 6- to 12-year-old boys with behavior problems. Problem identification, extent of impairment, cognitive/attentional, family context, and behavioral symptom differences were examined among 28 boys with ADHD, inattentive type; 9 with ADHD, hyperactive-impulsive type; 59 with ADHD, combined type; and 18 with no ADHD diagnosis. Some evidence for validity of ADHD was suggested, especially for the inattentive and combined subtypes, and on measures of impairment, mother-, father-, and teacher-rated disruptive symptoms, and observed playroom behavior. Few differences were obtained on measures of family context and age-corrected indices of cognitive/attentional functioning. Supplementary analyses of the boys with ADHD, combined type, subgrouped on the presence or absence of oppositional and conduct disorders, highlight the role of such diagnostic comorbidity in some of the dysfunctions attributed to ADHD.