Recruitment and Retention of Older People in Clinical Research: A Systematic Literature Review

Abstract

OBJECTIVE To identify barriers and solutions for the recruitment and retention of older (aged ≥65 years) people in clinical trials. DESIGN Systematic literature review. METHODS Three databases (Medline, Embase, and CENTRAL) were searched for articles reporting on barriers or solutions regarding the recruitment or retention of older people. Only original research articles were included. RESULTS Fifty eligible articles were identified. Exclusion criteria were the most common cause of poor recruitment of older adults (mainly age and comorbidities). Patients' families or physicians often advised against participation (22% of included studies). Lack of interest (18%) and problems with transportation (18%) were also commonly cited as challenges. Fourteen trials (28%) reported that monitoring and adapting their recruitment methods helped, along with a flexible research team (26%) and provision of transportation (24%). Retention was impaired by death (12%), illness (8%), and loss of interest (6%). Methods with a positive effect on retention included financial incentives and regular information about the progress of the study (12%), a low staff turnover (12%), flexibility in appointment making (10%), and expression of appreciation by the staff through letters, gifts, and cards to the participants (10%). CONCLUSION We identified several barriers and have listed potential solutions that may improve recruitment and lead to fewer dropouts in trials involving older populations. Implementation of our findings may help mitigate the manifold challenges that come with running a trial with older people.

Securing Participant Engagement in Longitudinal Substance Use Disorder Recovery Research: A Qualitative Exploration of Key Retention Factors

“…To our knowledge, this is the first paper that investigates research relationships as a factor in participant retention in longitudinal studies of SUD. This lack of specific focus on research relationships is also found in recent studies on other groups, such as older people [15] and individuals with eating disorders [35].…”

Recumbent cycling to improve outcomes in people with hip fracture: a feasibility randomized trial

“…Recruitment to clinical trials is recognised as being particularly challenging in acute orthopaedic settings and trials involving older people [ 30 , 31 ]. As illustrated in Fig.…”

“…Approximately 50% of those eligible consented to the study. Obtaining consent in time critical situations can be challenging [ 30 , 31 ], which is why we extended the recruitment window to 4 days. Despite this, it was not possible to obtain consent within four days for over a third of those who did not consent, mainly due to limited staff time.…”

Baseline characteristics and comparability of older multimorbid patients with polypharmacy and general practitioners participating in a randomized controlled primary care trial

“…On the other hand, even if older multimorbid adults are not explicitly excluded, major barriers to recruiting this type of study participants include limited mobility (e.g. not being able to attend multiple appointments or complete certain tests), and in the case of cognitive impairment, inability to provide informed consent [14,16,17]. Additionally, the person identifying and selecting patients for recruitment (e.g.…”