BackgroundTimely recruitment and effective retention of participants are challenging for clinical Parkinson's disease (PD) research studies. Not achieving this can affect delivery costs and bias results.ObjectiveTo identify successful recruitment and retention methodologies for clinical research studies in PD.MethodsWe conducted a systematic scoping review using a Population, Intervention, Comparator, Outcome and Study design (PICOS) framework to search and screen literature within five databases for published quantitative and mixed methods studies evaluating recruitment and retention strategies of interventional and observational trials in PD.ResultsSearches identified 4608 records, of which six papers covering eight studies were included in the review following screening for eligibility. No papers on retention strategies were found that met eligibility criteria. Effective strategies for rapid recruitment included research registries and trial finders (n = 3), digital marketing campaigns (n = 3), site recruitment support (n = 1) and multiple referral sources (n = 1). Recruitment diversity was increased by online campaigns, mandatory 10% minority targets set by funders and supplemental site funding.ConclusionsThis scoping review has identified methods that can be used to increase the rate and diversity of recruitment to PD clinical studies. Retention methodologies are under-researched.
Keywords: Parkinson's disease; clinical trial; observational study; patient recruitment.
Recruiting patients to clinical studies and ensuring participants complete them (known as “retention”) is challenging in Parkinson's disease (PD). If studies take longer this increases costs, and if the right people do not take part in studies this can mean that results may not be representative of the PD community. Our objective is to find out what effective strategies there are to support recruitment and retention to clinical research studies in PD. We reviewed literature within five study databases. We used the population, intervention, comparator, outcome and studies (PICOS) framework to create a search strategy based on our research question, and inclusion criteria for study selection. Important criteria were: (1) studies had to test a recruitment or retention strategy in a PD clinical research study, (2) studies had to provide evidence on how well the strategy worked. We found 4608 unique research papers, six of which described and evaluated recruitment strategies. No papers on retention strategies were found that met eligibility criteria. Successful recruitment strategies included digital marketing (n = 3), research registries (n = 3), supporting study sites (n = 1) and multiple sources to refer people with Parkinson's (PwP) to studies (n = 1). Recruitment of PwP from diverse backgrounds was enhanced by (1) online campaigns, (2) funders requesting that 10% of study participants come from diverse backgrounds 3) additional funding for research teams.This scoping review identified methods that can be used to increase the rate and diversity of recruitment to PD clinical studies. Retention methodologies are under-researched.