Abstract
Prisons are an important setting to reach an underserved group and reduce health inequalities. This study describes a co-design approach to developing a health promotion leaflet for young men in prison with the aim to evaluate the effects of the leaflet on behaviours in the wider prison population. We successfully co-designed a leaflet with a group of young men in a prison through a series of workshops. The leaflet was evaluated through a cluster randomised controlled trial, where it was distributed to young men in half the wings in the prison (with the other half as a control wings) and followed-up a week later with a short evaluation survey across all the wings. Although the leaflet was rated as highly acceptable with some significant shifts in attitudes, there were no significant differences in behaviours between the leaflet and control groups. Free text responses from participants highlighted the material and social constraints in adopting healthy behaviours, including the challenges of being locked up for long periods, limited opportunities to take-up healthy activities and choices, and restrictions to personal finances and support. The study highlights the value in the co-design approach but wider structural and policy support is required to create health promoting environments.