BACKGROUND AND AIMS While some digital supports aid in improving young people's mental health, there is a dearth of information regarding the most effective ways to involve young people in the co-production of digital technologies. User input is essential, particularly for marginalised young people who are often excluded. The aim of this scoping review was to examine recent literature on the most common co-production processes of digital mental health supports with marginalised young people.

METHOD A scoping review was conducted to identify literature published since 2021, written in English, focusing on co-production processes of digital mental health supports with marginalised young people aged 16-25. Basic information, data relating to the research question and key findings were extracted. A combination of Excel and Covidence management software was used to collate the charted data and manage the screening process. Studies were included if they used innovative youth-led approaches in the design, development, implementation or evaluation of digital mental health supports ranging from mental health promotion to targeted interventions.

RESULTS Out of 2341 studies initially screened, 21 studies published between 2021 and 2023 with a range of study designs and evidence were included. The studies reported on engagement with marginalised young people in the design, implementation, and/or evaluation of digital mental health technologies. The review examined qualitative and mixed methods studies from eleven countries, with most co-produced digital supports relating to mental health promotion and prevention. Most common were supports targeting general mental health and mental wellbeing. More than half of the studies included representation from LGBTQ+ young people, followed by ethnic minorities and migrants, but few included other marginalised groups. Only 6 of 21 studies used innovative approaches and many typically involved young people in only one of the co-production processes with design identified as most common. Finally, passive rather than active participation of young people was found to be pronounced. This limits young people's opportunities to shape the outcome to the data collection process only.

CONCLUSION Given the extent to which marginalised groups are actually involved in co-production, the review suggests the need for young people to be more actively involved in all co-production processes of digital mental health technologies. Offering a diverse range of methods through innovative, participatory approaches can facilitate more effective engagement from young people and provide an environment that is inclusive to a range of voices and perspectives. Lastly, the lack of inclusion of marginalised groups such as young people with a disability, or youth living in rural areas is an important issue to consider for future research.