Independent dimensions of hyperactivity and aggression: A validation with playroom observation data.

Abstract

Examined the validity of the 2-factor solution (Hyperactivity and Aggression) presented by J. Loney, J. Langhorne, and C. Paternite for symptom data from their study of 135 hyperkinetic/minimal brain dysfunction boys. The present sample consisted of 90 male referrals (from Grades 1 through 6) to an outpatient child psychiatric service. Hierarchical multiple regression analyses were performed on demographic data, mother and teacher rating scales, and observations made in 2 15-min playroom procedures (free play, restricted academic). Results support the validity of the differentiation of these 2 externalizing dimensions. The Hyperactivity factor made a unique contribution in accounting for the variance of numerous dependent variables, beyond the variance it shared with the Aggression factor. The Aggression factor made a unique contribution to few of these variables. In no case was the information supplied by the 2 symptom factors completely redundant.