Recruitment of older adults into randomized controlled trials: Issues and lessons learned from two community-based exercise interventions in Shanghai

There is a global imperative to increase awareness of the emerging evidence on physical activity (PA) among older adults. "Healthy aging" has traditionally focused on preventing chronic disease, but greater efforts are required to reduce frailty and dependency and to maintain independent physical and cognitive function and mental health and well-being.

Background Despite significant investment in infrastructure many trials continue to face challenges in recruitment and retention. We argue that insufficient focus has been placed on the development and testing of recruitment and retention interventions. Methods In this current paper, we summarize existing reviews about interventions to improve recruitment and retention. We report survey data from Clinical Trials Units in the United Kingdom to indicate the range of interventions used by these units to encourage recruitment and retention. We present the views of participants in a recent workshop and a priority list of recruitment interventions for evaluation (determined by voting among workshop participants). We also discuss wider issues concerning the testing of recruitment interventions. Results Methods used to encourage recruitment and retention were categorized as: patient contact, patient convenience, support for recruiters, monitoring and systems, incentives, design, resources, and human factors. Interventions felt to merit investigation by respondents fell into three categories: training site staff, communication with patients, and incentives. Conclusions Significant resources continue to be invested into clinical trials and other high quality studies, but recruitment remains a significant challenge. Adoption of innovative methods to develop, test, and implement recruitment interventions are required. Electronic supplementary material The online version of this article (doi:10.1186/1745-6215-15-399) contains supplementary material, which is available to authorized users.

Recruitment and retention of frail elderly in research studies can be difficult.