Familial subtypes of childhood hyperactivity.

On the basis of family history data we defined two subtypes of childhood hyperactivity: family history-positive (FH+), in which at least one biological parent of the child had a diagnosis in the antisocial spectrum; and family history-negative (FH-), in which neither parent had such a diagnosis. While children in both subgroups were equally deviant on measures of the core components of childhood hyperactivity (e.g., inattention and reactivity), the FH+ children were also deviant on dimensions of conduct disturbance and had siblings with a high prevalence of conduct disorder. FH- children showed little evidence of conduct disturbance, had more learning and academic problems, and had siblings with attentional and learning disabilities, but not conduct disorder. These findings suggest that the study of family constellations should be a fruitful method for resolving the heterogeneity of the hyperactive child syndrome.