Methods to Optimize Recruitment, Participation, and Retention Among Vulnerable Individuals Participating in a Longitudinal Clinical Trial.

Low-income and ethnic/racial minority adults do not often participate in research or may face unique barriers when participating in research, which delays and impedes medical advances for this vulnerable population. This article describes in detail the evidenced-based methods used to enhance recruitment, participation, and retention in a clinical trial at a center serving ethnic/racial minorities and low-income individuals. The article details the partnership with a community outreach center and describes the duties and impact of a community liaison to enhance recruitment, participation, and retention in a randomized controlled trial with a 6-month follow-up. Of the 246 individuals initially recruited for screening, 80 did not meet inclusion criteria with the most common reason for disqualification being meeting criteria for substance use disorder (n = 44). One hundred sixty-six participants qualified for participation. The majority of participants identified as African American (n = 127, 77.1%) and reported an annual individual income under $10,000 (n = 121 (74.2%). Forty-five percent of the sample completed the requested number of sessions (i.e., 12). Sixty-three percent of participants completed post intervention assessments and 42% completed 6-month follow-up data collection. The participation and retention numbers in this study appear higher than typical participation and retention rates in longitudinal studies with similar populations. The methods and lessons learned may be useful for other clinical trials that recruit vulnerable populations and wish to enhance participation, engagement, and retention.