Effects of parent and child characteristics on participation and outcome of an individualized booster parent intervention for children with externalizing behaviour

In this study, we examined whether a booster parent training, offered after a cognitive behavioural child intervention, is effective in reduction of aggressive behaviour and changes in parenting. A second aim was to identify parent and child characteristics that influence parental participation. Children (73% boys, 40% immigrants, mean age=10.1 (.53)) were randomly assigned to the child (n=97 children) or child and parent intervention (n=94 children) condition. Results of both intention-to-treat and completers only analyses indicated no extra effects of the parent intervention for the total group. Parents who participated (47%) did not differ from non-participants in demographic characteristics. However, mother's perceived level of child's aggression at the end of the child intervention was of significant meaning for the decision to participate in the parent intervention. Participation seemed to interrupt the development of more aggressive behaviour and less appropriate parenting skills for those children in highest need and resulted in increased maternal involvement.