Background

Homeless individuals with mental illness are challenging to recruit and retain in longitudinal research studies. The present study uses information from the Vancouver site of a Canadian multi-city longitudinal randomized controlled trial on housing first interventions for homeless individuals. We were able to recruit 500 participants and retain large number of homeless individuals with mental illness; 92% of the participants completed the 6-month follow up interview, 84% the 24-month follow up, while 80% completed all follow-up visits of the study.

Purpose

In this article, we describe the strategies and practices that we considered as critical for successful recruitment and retention or participants in the study.

Methods

We discuss issues pertaining to research staff hiring and training, involvement of peers, relationship building with research participants, and the use of technology and social media, and managing challenging situations in the context of recruitment and retention of marginalized individuals.

Conclusions

Recruitment and retention of homeless participant with mental illness in longitudinal studies is feasible. It requires flexible, unconventional and culturally competent strategies. Longitudinal research projects with vulnerable and hidden populations may benefit from extensive outreach work and collaborative approaches that are based on attitudes of mutual respect, contextual knowledge and trust.