Adolescents' Perspectives on Uptake, Engagement, and Implementation to Inform the Development of a Preventive Transdiagnostic Digital Mental Health Intervention: Qualitative Interview Study.

Interviews with 48 Swiss adolescents yielded 8 main topics and multiple subtopics on anticipated uptake, expected engagement, and implementation of preventive transdiagnostic DMHIs across person, intervention, system, and cross levels.

• 48 adolescents aged 12-21 years participated (mean age 16.52, SD 2.67; 32/48, 72.9% female).
• Single semistructured interviews were conducted in person or via video call between January and June 2022 in Switzerland.
• Interviews were audio-recorded, transcribed verbatim, and analyzed with hybrid deductive-inductive qualitative content analysis.
• Intercoder agreement was Cohen κ=0.72.

At the person level, mental health literacy, preuptake communication, and social networks were identified as important factors for anticipated uptake.

• Person-level factors highlighted the importance of mental health literacy, preuptake communication, and relevance of social networks.
• Recruitment was by voluntary response sampling via social media and the project website.

At the intervention level, adolescents emphasized usability, personalization, and privacy.

• These intervention characteristics were described as influencing anticipated uptake and expected engagement.
• The interviews were conducted in the predesign phase of a transdiagnostic preventive DMHI.

At the system level, adolescents expected adaptive, integrated, and low-threshold mental health services.

• System-level findings reflected expectations for adaptive, integrated, and low-threshold services.
• The authors conclude that implementation requires integration within adaptive care systems.

Trust and support emerged as cross-level factors for engagement.

• These themes spanned person, intervention, and system levels.

Participants described discrepancies between desired intervention characteristics and practical implementation, particularly for personalization, anonymity, peer exchange, and human support.

• Adolescents desired immediate human-delivered support, which conflicts with the self-guided nature of preventive DMHIs.
• The authors state this tension underscores the need for clear clinical boundaries and explicit escalation pathways.

Successful implementation of preventive DMHIs requires attention beyond intervention design.

• Needed elements include preuptake communication strategies, mental health literacy promotion, and integration within adaptive care systems.
• The study addresses a gap because existing research has predominantly relied on quantitative methods and only partly captured adolescents' perspectives.