A meta-analytic examination of comorbid hyperactive-impulsive-attention problems and conduct problems.

The author quantitatively reviewed prevalence rates, defining features, associated features, developmental trajectory, and etiology to examine 3 taxonomic questions about comorbid hyperactive-impulsive-attention problems (HIA) and conduct problems (CP): Do HIA and CP co-occur randomly? Does comorbid HIA-CP differ from HIA-only and CP-only? Do HIA and CP combine synergistically? Results showed that HIA and CP co-occur at a greater than random rate, that comorbid HIA-CP differs from HIA-only and CP-only in multiple ways, and that there is little evidence that HIA and CP combine synergistically. However, sample type, grouping definition, age, gender, and subtype of disruptive behavior often moderated these findings. Overall, the review suggests that HIA-CP is best conceptualized as an additive combination of HIA and CP rather than as a distinct category.