The aim of this study is to evaluate the efficacy and acceptability of the website "ich bin alles" (https://www.ich-bin-alles.de/) to improve depression literacy (knowledge about depression, which aid the recognition, treatment or prevention of depression) in parents of adolescents with acute or remitted depressive disorder. The investigators will examine whether the website improves depression literacy in parents of adolescents aged 12 to 18 years with a history of depression. The investigators will also assess the acceptability of the website among the participants.

Few young people with major depressive disorder seek professional treatment in time. Concerns about social stigma, confidentiality, and limited knowledge about mental health conditions, such as depression, or mental health services are some of the main barriers to seek treatment. Increasing parents' knowledge about and attitude towards depression and mental health in childhood and adolescence is important to increase parents' awareness towards their children's mental health and reduce possible prejudices and barriers towards depression and treatment. These aspects might contribute to more parents seeking professional help and treatment for their children at an early point of time in the course of a depressive disorder. To address these issues and contribute to knowledge gain, we developed an evidence-based website "ich bin alles" (https://www.ich-bin-alles.de/) with two separate sub-websites for (1) adolescents and (2) parents to improve depression literacy in these groups.

To improve depression literacy in parents, the website provides general information for parents about depression in childhood and adolescence (e.g., symptoms, causes, course and treatment of depression). Furthermore, the website provides information about strategies for parents on how to support their children if they are affected by depression and on appropriate prevention strategies; i.e., strategies for promoting mental health (e.g., providing a healthy environment, reducing stress, undertaking positive activities, positive parenting), 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 parents of adolescents aged 12 to 18 years with a history of depression, as well as parents of healthy adolescents aged 12 to 18 years. Easy access to information about depression would make early recognition of depression more likely and engage parents to help their children to seek help for depression.

Since the website targets two different groups, the investigators will evaluate the website accordingly:

Target group 1: Parents of adolescents with a major depressive disorder (acute or remitted) Target group 2: Parents of healthy adolescents (without a mental health condition)

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

The primary aim of this study is to evaluate the efficacy and acceptability of the website "ich bin alles" (https://www.ich-bin-alles.de/) to improve depression literacy in parents of adolescents with acute or remitted depressive disorder.

Inclusion Criteria:

• The presence of a current or remitted diagnosis of a mild, moderate, or severe major depressive episode according to ICD-10 Criteria: F32.0; F32.1; F32.2, F33.0, F33.1, F33.2) in the participants' children is assessed using a semi-structured clinical interview: the "Kinder-DIPS". The Kinder-DIPS is a well-established German interview for the diagnosis of a wide range of axis I psychiatric disorders in children from ages six to 18.

Exclusion Criteria:

• Insufficient knowledge of German

Data in our study contains sensitive participant information, such as sociodemographic information and information on comorbidities. Since participants could possibly be identified by making our raw data publicly available, ethical principles of protecting participant confidentiality would be breached. Aggregated group data can be made available upon request.