Barriers and Facilitators to The Involvement of Under-Represented Children and Young People (aged 8-25) in Mental Health Research - a Systematic Review.

Young people's involvement in mental health research enhances its relevance and impact. Involvement means conducting research with young people rather than just about them. However, under-representation persists among certain groups of young people, including ethnic minorities, those with disabilities, from lower-income households, with immigrant backgrounds and young people communicating in a language other than their first language. This systematic review applies the Behaviour Change Wheel (BCW) to explore barriers and facilitators to involving under-represented young people in mental health research and identify potential strategies for improvement. Five electronic databases and grey literature were systematically searched. Included studies focussed on children and young people (aged 8-25) from under-represented backgrounds involved in mental health research. The BCW was used to categorise barriers and facilitators as well as to map strategies to Intervention Functions. Five young people formed an oversight group, with three serving as co-researchers, contributing to search design, screening, data extraction and discussion. Twenty-seven studies from seven countries met the inclusion criteria. The majority of barriers and facilitators were linked to physical and social opportunity. Digital exclusion, time constraints, bureaucratic hurdles and mistrust of researchers were all barriers. Facilitators included flexible structures, inclusive communication and relationship building. Reported strategies to improve involvement aligned with enablement and environmental restructuring. Inclusive, adaptive research practices and improved reporting are needed to meaningfully engage under-represented young people in mental health research. Future research should prioritise perspectives of under-represented young people to better understand and address the barriers they face.