BackgroundAdolescents are at risk of developing depressive symptoms. Given the prevalence, recurrence and negative consequences of adolescent depression, it is crucial to implement prevention programs for high-risk adolescents. Prevention programs at an indicated level have shown to be successful in reducing depressive symptoms in adolescents. This study will evaluate the (cost)effectiveness of the prevention program ‘Op Volle Kracht (OVK 2.0)’ for adolescents with elevated depressive symptoms.MethodsWe will perform a Randomized Controlled Trial (RCT) with an intervention and control condition to test the effectiveness of an indicated prevention program aimed at depression in adolescents. Adolescents in their second year of secondary education (11–15 year) will be screened for depressive symptoms. Those with heightened levels of depressive symptoms (CDI-2 ≥ 14) will be randomly assigned to the intervention (N = 80) or control group (N = 80). The participants in the intervention condition will receive a prevention program comprising eight meetings of 60 min each. The participants in the control condition will receive psycho-educational information. All participants and their parents will complete assessment at baseline, post-intervention, and 6-, 12- and 24- month follow-up. Primary outcome will be depressive symptoms. Additionally, the present study will identify mechanisms that mediate and moderate the program effects and test the effect of OVK 2.0 on secondary outcomes.DiscussionThis paper describes a study designed to screen adolescents for depressive symptoms and offer them a prevention program to prevent the onset of depressive symptomatology. Adolescents in the intervention condition are expected to show lower levels of depressive symptoms at 12 month follow-up compared to adolescents in the control condition. If OVK 2.0 proves to be effective, the screening and intervention program could be implemented in schools on a large scale.Trial registrationDutch Trial Register NTR5725. Date registered: 11th of March 2016.

Background: Adolescent depression is a global mental health concern. Identification and effective prevention in an early stage are necessary. The present randomized, controlled trial aimed to examine the effectiveness of Cognitive Behavioral Therapy (CBT)-based depression prevention in adolescents with elevated depressive symptoms. This prevention approach is implemented in school communities, which allows to examine effects under real-life circumstances. Methods: A total of 5222 adolescents were screened for elevated depressive symptoms in the second grade of secondary schools; 130 adolescents aged between 12 and 16 years old (M = 13.59; SD = 0.68; 63.8% girls) were randomly assigned to the experimental (OVK 2.0) or control condition (psycho-education). Self-and parent-reported depressive symptoms were assessed at pretest and post intervention, as well as 6-and 12-months follow-up. Clinical assessment of depression was assessed at pretest and 6-months follow-up. Results: Intent-to-treat analyses revealed that the decrease in adolescent-rated depressive symptoms was significantly larger in the intervention condition than in the control condition. There was no significant difference in decrease of parent-rated depressive symptoms between both conditions. Conclusions: Based on the findings, we recommend the implementation of screening and prevention in schools, according the basics of this study design. Since this is a new step forward, we discuss the clinical impact and challenges, as well possibilities for future research. Trial registration: The study is registered in the Dutch Trial Register for RCT's (NTR5725). Date registered: 11 March 2016.

Depressive disorders are highly prevalent during adolescence and they are a major concern for individuals and society. The Response Style Theory and the Scar Theory both suggest a relationship between response styles and depressive symptoms, but the theories differ in the order of the development of depressive symptoms. Longitudinal reciprocal prospective relationships between depressive symptoms and response styles were examined in a community sample of 1343 adolescents. Additionally, response style was constructed with the traditional approach, which involves examining three response styles separately without considering the possible relations between them, and with the ratio approach, which accounts for all three response styles simultaneously. No reciprocal relationships between depressive symptoms and response style were found over time. Only longitudinal relationships between response style and depressive symptoms were significant. This study found that only depressive symptoms predicted response style, whereas the response style did not emerge as an important underlying mechanism responsible for developing and maintaining depressive symptoms in adolescents. These findings imply that prevention and intervention programs for adolescents with low depressive symptoms should not focus on adaptive and maladaptive response style strategies to decrease depressive symptoms, but should focus more on behavioral interventions.