Patterns of change in family-based aggression prevention.

Patterns of change on three intervention targets were examined in 151 families that participated in a family intervention designed to reduce and prevent children's aggressive behavior. Measures of parents' alliance and parenting skills and children's aggressive behavior were obtained at five times during the intervention. Three cluster analyses were conducted to identify patterns of change on each target. Linear and nonlinear patterns of improvement as well as two distinct patterns of no change were obtained. The patterns were differentiated by net improvement, overall level of skill, and trajectory of change. Family characteristics also differentiated the patterns and relations were found among patterns across intervention targets. The clinical implications of these findings are discussed.