Web-based Self-help Intervention Promoting Mental Health in Adolescents

This study aims to evaluate the feasibility and effectiveness of a web-based self-help intervention promoting mental health in adolescents. We will examine whether this intervention improves positive affect, reduces stress and alleviates negative affect and depressive symptoms in adolescents aged 12 to 18 years. We will also investigate the rates of adherence among the adolescents who use this web-based intervention and the acceptability of the intervention with adolescents.

The prevalence of mental health problems including depression rises during adolescence. Nevertheless, young people often have little knowledge about mental health problems and conditions, such as depression, and how they can be prevented. Besides limited knowledge, concerns about social stigma, confidentiality and limited access to mental health services are some of the main barriers to seek help. Therefore, highly acceptable and easily accessible services promoting mental health, such as knowledge about mental health conditions and effective self-help strategies to prevent them, are urgently needed for adolescents.

We developed a website, which provides evidence-based information about depressive disorders in youth (e.g., identification, etiology, treatment, and prevention of depression) and will be launched in autumn 2021. Furthermore, the website provides information about self-help strategies (e.g., reducing stress, doing exercise, undertaking positive activities), which are meant to serve as an addition to professional treatments of depression or to promote mental health in adolescents. Target groups of the website are adolescents aged 12 to 18 years seeking help for depression, as well as healthy adolescents seeking information about mental health promotion or prevention of depression.

To increase the acceptability of the website and the engagement of young people, the website will integrate continuously updating content consisting of short exercises based on principles of positive psychology. This web-based self-help intervention is thought to provide a mode of delivery (the combination: "online" \& "positive psychology"), which is acceptable and engaging to youth, and might effectively promote mental health in adolescents.

Since the website targets two different groups, we will evaluate the web-based self-help intervention accordingly:

Target group 1: Adolescents with a major depressive disorder (acute or remitted) Target group 2: Healthy Adolescents (no mental health condition)

The current study will focus on target group 2. A study focusing on target group 1 can be found in a separately registered clinical trial on clinicaltrials.gov.

The primary aim of the study is to evaluate the feasibility and effectiveness of this web-based self-help intervention to improve positive affect, reduce stress, alleviate negative affect and depressive symptoms in adolescents.

Participating young people will be randomized to either the web-based intervention group or a web-based control group (i.e. sham intervention / comparator). All participants will be evaluated at pre-, post-intervention, and at a two-week follow-up.

Hypothesis: Participants in the web-based intervention group will report a significant decrease of negative affect, depressive symptoms and perceived stress compared to participants in the web-based control group. Participants in the web-based intervention group will report a significant increase of positive affect compared to participants in the web-based control group

Eligibility Criteria:
Inclusion Criteria:

* Intelligence quotient (IQ) of ≥ 80

Exclusion Criteria:

* Current diagnosis of a mental disorder
* Remitted depressive disorder
* Insufficient knowledge of German