Where are the Public in Prevention Science? A Scoping Review of Public Involvement in the Development and Evaluation of Family-Based Prevention Interventions.

Public involvement (PI) - research conducted with or by members of the public - is increasingly recognised as essential to high-quality intervention research. However, its role in Prevention Science, including within family-based interventions, remains unclear. We conducted a scoping review following Arksey and O'Malley (2005), Levac et al. (2010) and JBI guidance (Peters et al., 2020). Peer-reviewed empirical studies published between January 2022 and December 2024 that reported the development, implementation or evaluation of community-based family prevention interventions were eligible. Searches across four databases identified 540 eligible studies at title/abstract screening. Using a fixed-interval random sampling approach, 81 full texts were reviewed, and 54 studies were included for in-depth analysis (≈ 10% of eligible papers). Data extraction captured the presence, scope, terminology, frameworks, and reported outcomes of PI. Only 3.7% (2/54) of included studies explicitly reported PI, with a further two describing its presence in linked publications from earlier phases of the same research. Within the analytic sample, explicit reporting of public involvement was uncommon across the range of countries, intervention types and research stages represented. Where present, PI was largely confined to intervention development, with no examples of PI informing the design or conduct of evaluations. No study used established PI frameworks (e.g., GRIPP2, Involve). Among the 50 studies with no identified PI, 26/50 (52%) collected participant feedback on intervention experiences, but this was conceptually distinct from PI. Public involvement in research on family-based prevention interventions appears extremely limited. Possible explanations include a genuine lack of PI activity, underreporting, and conceptual confusion between PI and participant feedback. Strengthening PI in Prevention Science will require clearer definitions, shared terminology, capacity building for researchers and public partners, and stronger expectations from journals and funders. Improved reporting will support cross-study learning and the development of good practice.