Preventing Depression in Adolescents: A Prospective Trial of Two Universal Prevention Programs

Abstract

This study evaluated two universal programs for the prevention of depressive symptoms in adolescents. Three hundred eighty students from suburban/rural high schools were randomly assigned to a cognitive behavioral program (CB), an interpersonal program (IPT-AST), or a no intervention, assessment only control. The interventions involved eight 90-minute weekly sessions run in small groups during 9th grade Wellness classes. At post-intervention, students in both interventions reported significantly lower levels of depressive symptoms than the no intervention group, controlling for baseline scores; the two intervention groups did not differ significantly from each other. The effect sizes for the CB intervention and the IP intervention were .37 and .26, respectively, representing small to moderate effects. To examine differences in response in relation to level of risk, adolescents with baseline depression scores one standard deviation above the mean or greater were identified as high-risk. For these high-risk adolescents, the effect sizes for the CB intervention and the IP intervention were .89 and .84, respectively. The observed effects were best described as a prevention effect for low-risk adolescents and a treatment effect for high-risk adolescents. Affiliative and achievement orientations moderated the effect of the interventions. No group by gender interactions were found. Attributional style partially mediated the effect of the CB intervention on depressive symptoms. No group differences were found at the six-month follow-up.