Table 2.

Effective Recruitment Strategies

Reference	Sample	Design	Effective recruitment strategies
Castro et al. (under review)	35 Latinx males and females with pre-diabetes	Cross-sectional, mixed methods	Developed a balanced sampling frame for equity based on gender, age, and acculturation status Identified eligible individuals from a diabetes registry and contacted them by letter of invitation and email The study’s bilingual-bicultural Project Director contacted interested individuals via telephone, provided informed consent information, and invited them to an in-person session At this in-person session, individuals were read the informed consent in their preferred language. Upon signing, they could participate in the interview at that time or at another scheduled time. To establish rapport, and recognizing the vulnerability of low-acculturation individuals and low literacy in some, for data quality, we administered all instruments via interview.
Chen et al. (under review)	513 racial-ethnic minority nurses	Cross-sectional	Partnered with key nursing associations/organizations (e.g., National Association of Hispanic Nurses, Asian American/Pacific Islander Nurses Association, Philippine Nurses Association of America), particularly critical to reach racial-ethnic minority nurses. Utilized user-friendly platforms for distressed frontline workers amid the SARS-CoV-2 pandemic. Participants could access online survey via QR code or link in flyer. Included in recruitment flyer statements to thank and honor nurses’ significant contributions and efforts put into patient care during the pandemic Consulted with nurses to determine appropriate incentive
Petrov et al. (2017)	19 adolescent, female victims of sex trafficking and/or abuse at an in-patient group home	Cross-sectional	Investigators and staff completed rigorous screening process to become volunteers at the group home Partnered with CEO and directors of the group home Approached participants during regularly scheduled programming Offered needs assessment for healthy lifestyle programming Asked each participant for preferred gift within a low-denomination compensation package
Langer et al. (2018)	40 hematopoietic cell transplant recipient/caregiving partner dyads	Intervention; single-group pre-post	Partnered with provider willing to champion study Met participants where they were; scheduled approach and consent sessions through clinic to accommodate medical appointments Approached patients and partners at presumed time of readiness relative to transplantation, avoiding difficult inpatient hospitalization phase and period of extreme patient immunosuppression Couple-based intervention afforded psychosocial support not just for patients but for caregiving partners/ spouses as well; this stood out from the typical medical studies offered.
Davis et al. (2019)	503 women with elevated sexual risk history	RCT	Advertised on social media platforms and print media frequently used by young women Recruited through flyers in local venues frequented by young women, including coffee shops, beauty salons, and sexual health clinics Provided postcard-sized flyers to participants to hand out to their friends, improving word-of-mouth recruitment Recruited staff of a similar age and gender to potential participants to increase comfort level
Davis et al. (2020)	209 men with self-reported sexual assault history and heavy episodic drinking	RCT	Placed ads in venues targeting young adult drinkers, such as bars and local happy hour locales Conducted eligibility screening via online survey versus telephone, for greater sense of anonymity Offered flexible session scheduling, including weekend options Staff trained to fully describe protection of participant privacy and confidentiality Offered transportation vouchers for participants to attend in-person session
Joseph et al. (2019)	60 insufficiently physical active African American women with obesity	Pilot RCT	Used paid online social media advertisements (i.e., Facebook) that linked to study website; website provided detailed information about study and access to online screening tool. Placed paid advertisements in African American-focused newspapers and social networking websites Promptly followed-up with interested individuals (i.e., ideally within 24-48 hours of initial contact) to further describe study purpose and further screen for eligibility Created and utilized manualized telephone recruitment scripts to provide detailed overview of study procedures, setting clear participant expectations
Kim et al. (in preparation)	96 hematopoietic cell transplant recipient/ primary caregiver dyads	RCT	Collaborated with treating cancer center and providers Approached patients and caregivers during an already scheduled post-transplant outpatient visit Emphasized the dyadic aspect of the study, supporting not just patients but primary caregivers
Menon/ Larkey et al. (2020)	419 unscreened or due for colorectal cancer screening	RCT	Hired study recruitment/implementation staff from the communities to be reached Engaged community sites in low income zip codes to obtain service population sociodemographic characteristics (age, race, ethnicity); this informed selection of sites to maximize targeted enrollment Adapted initial prospective participant contact contexts based on community site leaders’ suggestions (e.g., lunch gatherings at senior centers) Included broad types of community venues, adapting message strategies to reach the intended age group: churches, schools, community centers, residential centers Included novel public sites, such as fitness centers, food trucks, and farmer’s markets
Lee, Reese-Smith et al. (2017)	310 African American and Hispanic or Latina overweight/ obese, sedentary women	RCT	Employed multiple modes of approach/ advertising Face-to face announcements at community events and meetings (e.g., church or university campus meetings, health fairs) Advertisements or announcements with local newspapers or magazines Advertisements or announcements on a listserv or on the Internet Advertisements or announcements on television or radio
Lee et al. (2017)	89 children or their parents attending early care and education centers in neighborhoods with high proportions of individuals who identify as Hispanic	Cluster RCT	Recruited mothers of preschoolers (with child assent) from already identified sites via classroom announcements, flyers, and teacher encouragement
Reifsnider et al. (2018)	175 Mexican American mother/infant dyads	RCT	Partnered with county health department and their WIC clinics Provided presentations to WIC staff about study and socialized with them Hired promotoras (clinical health workers) who were bilingual/bicultural in English/Spanish Promotoras recruited participants when the women came for their WIC enrollment WIC staff promoted study to WIC participants and collaborated in allowing promotoras time to recruit inside and outside of clinic All recruitment materials in English/Spanish Recruitment tables prominently displayed at WIC clinics Promotoras were pro-active in recruitment and inquired of pregnant women receiving clinic services if they were interested in the study Obtained county WIC approval to recruit at additional WIC clinics to meet recruitment goal
Vander Wyst et al. (2020)	117 Latino adolescents with prediabetes	RCT	Collaborated with established and trusted community entities as co-investigators Employed bilingual/bicultural research staff and recruitment materials Cast a wide net of referral sources across multiple sectors (clinic, community, and media) Clinic efforts led by project physician with ongoing engagement Established Business Associate Agreements with health centers to share protected health information for consented participants Conducted recruitment presentations with physicians, nurses, health educators, and registered dietitians to establish relationships, provide project updates, and coordinate recruitment activities Sent monthly reports to clinics to track all patients who were referred Community efforts led by community partners (community coalitions, health fairs and churches) Media efforts advertised through Spanish language outlets and posted through social media Employed snowball sampling (word-of-mouth from past participants and families) Provided results of laboratory testing back to participants Focused on a health topic highly relevant to priority population Provided access to health promotion intervention otherwise not available Offered weekend screening and enrollment visits Offered monetary (cash) reimbursement for time and travel Provided transportation and parking
Youngstedt et al. (2021)	71 veterans with PTSD	RCT	Veteran served as a research coordinator, helped with feelings of trust and credibility Received referrals from mental health professionals at the VA Placed study ads in military newspaper Placed study flyers throughout mental health clinic at VA

Note. PTSD = post-traumatic stress disorder; RCT = randomized controlled trial; WIC = women, infants and children. Terms used to describe samples with regard to race and ethnicity differ across studies due to variations in usage and preference, and to denote specificity when possible, e.g., Mexican American.