Barriers and facilitators to recruiting older adult care home residents into clinical trials of medicines and vaccines: a scoping review

INTRODUCTION: Excluding Care Home (CH) residents from clinical trials of medicines and vaccines has led to an evidence gap. Findings from younger adults may not be generalisable to CH residents with frailty and dementia. Therefore, it is essential to evaluate pharmacological treatments directly in CH residents to assess their safety and efficacy. METHODS: As part of the Widening Access to Trials in Care Homes project, we conducted a scoping review using Joanna Briggs Institute methodology to identify barriers and facilitators to recruiting CH residents into clinical trials of medicinal products. We searched EMBASE, MEDLINE, PsycINFO, CINAHL, and the Cochrane Library (1990 to January 2025). Quantitative data on screen failures and dropouts, and qualitative data on trial teams' real-world experiences and stakeholder perspectives were extracted, synthesised into themes and presented as descriptive summaries. RESULTS: From 14,301 records, eight articles were included (2002 to 2021) from the USA (N = 4), UK (N = 3) and France (N = 1). Six were RCTs, and two were a qualitative sub-study and a questionnaire survey. Screen failure rates ranged from 18% to 96%. Identified themes of barriers and facilitators were study design, selection criteria, recruitment methods, data collection methods, participant retention, CH resident and family-related factors, CH facility and staff-related factors, healthcare professional involvement, logistical and operational factors, consent-related factors, ethical and regulatory considerations, insurance and trial costs, and generalisability of trial results. CONCLUSIONS: Our review specifically identified key barriers and facilitators to recruiting CH residents into pharmacological trials. These findings can guide trial planning and support evidence-based care for this vulnerable population.