AUTHOR=Kloek Maria W. H. , Zsigo Carolin , Primbs Regine , Iglhaut Lucia , Kaubisch Sara , Piechaczek Charlotte E. , Keim Pia-Marie , Feldmann Lisa , Schulte-Körne Gerd , Greimel Ellen TITLE=Improving adolescents’ knowledge about mental health and depression: a randomized experimental study of web-based information JOURNAL=Frontiers in Digital Health VOLUME=Volume 7 - 2025 YEAR=2025 URL=https://www.frontiersin.org/journals/digital-health/articles/10.3389/fdgth.2025.1640366 DOI=10.3389/fdgth.2025.1640366 ISSN=2673-253X ABSTRACT=Adolescents often lack adequate knowledge about mental health and available professional support, which hinders timely help-seeking. As many adolescents seek information online, providing reliable web-based resources may enhance their mental health literacy. This randomized experimental study (preregistered at ClinicalTrials.gov: NCT05300217) examined the effectiveness and reception of innovative online information designed to improve adolescents’ knowledge of depression and mental health. A total of 77 adolescents aged 12–18 years were randomly assigned to one of two conditions: (1) web-based information on depression or (2) web-based information on strategies to promote mental health. Both interventions were derived from the evidence-based website “ich bin alles” (English translation: “I am everything”). Primary outcomes were knowledge of depression and knowledge of strategies to promote mental health, assessed immediately after the intervention and at 2- and 4-week follow-ups. Secondary outcomes included perceived visual aesthetics, ease of use, utility, and enjoyment. Adolescents showed significant increases in knowledge of depression [F (3, 76.67) = 13.29, p < .001] and knowledge of strategies to promote mental health [F (3, 76.41) = 7.89, p <.001] over time, attributable to the assigned information. Participants also rated the website's visual aesthetics, ease of use, utility, and enjoyment positively. Age-appropriate, visually appealing web-based information effectively improved adolescents’ knowledge of depression and mental health. Freely accessible, evidence-based online resources represent a scalable strategy to strengthen mental health literacy among young people.