RESUMEN
INTRODUCTION: Barriers to recruitment for dementia studies are well documented. As part of the UK government's Dementia 2020 strategy, a nationally consistent system to increase public engagement and participation in research was launched in February 2015. METHODS: We describe the development of the "Join Dementia Research" registry, including evolution of policy, involvement of people with dementia in co-production, data requirements, governance, technology, and the impact on study recruitment and what factors may have contributed to the services success. RESULTS: The UK-wide online, telephone, and postal service has registered 47,071 volunteers, with 33,139 people (67.9% of all volunteers) taking part in 378 studies, with 49,954 total study enrolments. This has taken place across 295 research sites, involved 1522 researchers, and resulted in 134 peer-reviewed publications. DISCUSSION: Public registries of individuals interested in research, with user-provided data enabling basic phenotyping, are effective at increasing public engagement with research and removing barriers to study recruitment. Deeper pheno/genotyping could be undertaken to improve matching, but how and when that information is collected will be a key factor.