Optimizing participant recruitment and retention in clinical studies by hearing the voice of persons with Parkinson's

BackgroundRecruitment and retention remain major barriers to clinical research in Parkinson's disease (PD).ObjectiveWe reviewed the literature on barriers and facilitators to PD research participation, and explored motivations, perceptions, and preferences regarding clinical research participation among "underrepresented" populations (URPs) in Asia.MethodsWe reviewed published studies examining recruitment and retention in PD research. In parallel, questionnaires were administered to patients in Malaysia and Kyrgyzstan (n = 92) to assess motivations for participation, project-related preferences, and willingness to engage in different types of research. Findings from the literature and survey, and the authors' real-world research experiences were synthesized to identify practical strategies for improving participation.ResultsKey barriers identified from the literature included limited awareness of research, logistical and financial burden, disease-related disability, mistrust, stigma, and technological challenges. Across both Asian cohorts, altruistic motivations, trust in clinicians and researchers, perceived personal and societal benefit, and appreciation of healthcare services strongly influenced willingness to participate in research. Minimizing inconvenience and avoiding invasive procedures were rated as important. Most patients were willing to participate in longitudinal studies, digital monitoring, and biosample collection involving saliva, blood, urine, and stool, whereas cerebrospinal fluid sampling and brain donation were less acceptable. Solutions include integrating research into routine care, culturally-sensitive communication, patient-friendly study designs, return of research results, active engagement of URPs, and greater patient involvement throughout the research process.ConclusionsBarriers to PD research participation are multifactorial. Patient-centred, culturally-sensitive, and trust-based approaches that reduce burden while enhancing inclusivity and communication may promote more sustainable research programs.