Evaluating 1 Running head: EFFECTIVENESS OF UNIVERSAL PREVENTION The Effectiveness of Two Universal Preventive Interventions in Reducing Children’s Externalizing Behavior: A Cluster Randomized Controlled Trial

This paper reports the effectiveness of two universal prevention programs in reducing externalizing behavior in elementary school children. A sample of 1,675 first graders in 56 Swiss elementary schools was randomly assigned to a school-based social competence intervention, a parental training intervention, both, or control. Externalizing psychopathology and social competence ratings were provided by the children, primary caregivers, and teachers at the beginning and end of the 2-year program, with a follow-up 2 years later. Intention-to-treat analyses revealed that long-term effects on teacherand parent-rated externalizing behavior were greater for the social competence intervention than for the control. However, for most outcomes, no statistically significant positive effects were observed.