Abstract
BACKGROUND: Randomised controlled trials (RCTs) are often considered the gold standard in research design to determine clinical and cost-effectiveness, and yet the majority are not considered "informative" or otherwise useful for decision-makers in research, clinical practice, and policy. What constitutes an informative trial of digital mental health interventions (DMHIs) for children and young people (CYP) remains unclear. By investigating the perspectives of researchers and young people, this study highlights key components that enhance the relevance, rigour, and impact of youth DMHI trials. METHODS: This multi-method qualitative study, guided by a pragmatist approach, explored the perspectives of researchers, with expertise in DMHIs, and young people, with lived experience of mental health conditions and DMHI use, on what is an informative DMHI trial for CYP (RQ1) and what contributes to informativeness (RQ2). Semi-structured interviews with researchers were analysed using reflexive thematic analysis, whilst the content of participatory group workshops with young people were summarised in relation to researcher-generated themes. RESULTS: Seven researchers and six young people participated. Four themes and 10 sub-themes were generated for what an informative trial is: 1) Addresses questions important to partners; 2) Feasible to conduct; 3) Trustworthy and credible, and 4) Accessible and safe. Three themes were generated as contributors to informativeness, including 5) Partner involvement; 6) Researcher and site capacity, and 7) The wider context. Both groups recognised the importance of informative trials, but researchers emphasised methodological rigour and logistics, whereas young people focused on broader concerns such as the impact of power dynamics. CONCLUSIONS: This study highlights core components of informativeness in DMHI trials for CYP and demonstrates the value of involving both academic and non-academic contributors in shaping informativeness.