Treatment of oppositional defiant and conduct problems in young Norwegian children Results of a randomized controlled trial

The efficacy of the Incredible Years parent training and child therapy programs was examined in a randomized controlled study including 127 Norwegian children aged 4-8 years. Children diagnosed with oppositional defiant disorder (ODD) or conduct disorder (CD) were randomized to parent training (PT), parent training combined with child therapy (PT + CT), or a waiting-list control condition (WLC). Assessments were carried out at baseline, posttreatment and at a one-year follow-up using standardized measures and a semi-structured interview. Both active treatment conditions reduced child conduct problems posttreatment as opposed to the WLC, while differences between the two treatment conditions were small and nonsignificant. About two thirds of the treated children functioned within normal variation after treatment, and the same proportion no longer received an ODD diagnosis at the one-year follow-up. Parental use of positive strategies increased after treatment, and the use of harsh and inconsistent discipline decreased as did mother experience of stress. The outcome of this study emphasizes the importance of offering parent training to young children with severe conduct problems exhibited at home. The findings and usefulness of the Incredible Years program in the present Norwegian replication study further support and extend positive outcomes of previous controlled trials conducted primarily in Anglo-Saxon countries.