DOI: 10.5061/dryad.n02v6wx79
title: Recruitment and retention strategies for improving representation in clinical research: A meta-synthesis

description: The objective was to identify innovative strategies that may increase
 recruitment and/or retention of groups less represented in chronic disease
 clinical research. A systematic review was conducted. Inclusion
 criteria were: (a) NIH-defined racial and ethnic minority groups and
 clinical research; (b) evidence-based, clinical research recruitment
 and/or retention strategies involving the leading causes of mortality and
 morbidity in the United States; (c) conducted in the United States; and
 (d) qualitative design. Data exploring the strategies were extracted and
 thematically analyzed. Twenty-seven studies were included.
 Studies focused on cancer (70%), recruitment (93%), and perspectives from
 clinicians (63%). The most referenced strategies were education (44%),
 communication (48%), and community-based participatory research (63%).
 Critical themes include empowerment, transparency, trust, and
 sustainability. Strategies must prioritize the community and be
 implemented sustainably, where cultural humility and community-based
 participatory research are foundational.
description: We adhered to and adapted the Enhancing Transparency in Reporting
 the Synthesis of Qualitative Research (ENTREQ) guidelines, Enhancing the
 Quality and Transparency of Health Research (EQUATOR) guidelines, and The
 Preferred Reporting Items for Systematic Reviews and Meta-Analyses
 (PRISMA) checklist to report this completed systematic review and
 meta-synthesis. <strong>Eligibility
 criteria</strong> Briefly, we included studies
 with qualitative or mixed methods research designs, were conducted in the
 U.S., published in English or Spanish in a peer-reviewed journal between
 2009 and 2024, and that demonstrated evidence-based recruitment and/or
 retention strategies for clinical research focused on the leading causes
 of morbidity and mortality in the U.S. as determined by the Centers for
 Disease Control and Prevention (CDC). Studies spanning ten years from 2009
 were initially selected; this was later updated to include fifteen years
 from 2009 to reflect the increasing significance and importance of this
 work during this period. Eligible studies targeted ethnic and racial
 minorities defined by the NIH. Studies included all ages and used the NIH
 definition of clinical research.
 <strong>Information sources and search
 strategy</strong> The literature search strategy
 was developed in collaboration with the review team and trained biomedical
 librarians (NT and AL) at the National Institutes of Health (NIH). The
 search strategy was created using a combination of text words and the
 controlled vocabulary terms in the following databases: (PubMed (MeSH)
 Medical Subject Headings, Embase - EMTREE, and CINAHL subject headings.
 The search was refined using an iterative process and finalized by the
 review team members and librarians. For each search strategy, the search
 terms included these text words and controlled vocabulary when available:
 underrepresented, minority, racial and ethnic groups, clinical research,
 and disparities. The following databases were searched: PubMed (National
 Library of Medicine), Embase (Elsevier), CINAHL Plus (Cumulative Index to
 Nursing and Allied Health Literature - EBSCOhost), and Web of Science Core
 Collection (Clarivate Analytics). The following limits were applied using
 the filters available in each database. The search was limited to human
 studies only and was limited to studies conducted in the United States.
 The final search strategy can be found in the S2 Appendix.
 <strong>Selection process</strong>
 Covidence systematic review software (Veritas Health Innovation,
 Melbourne, Australia; www.covidence.org)
 imported studies and automatically excluded duplicates. All stages of the
 screening, data extraction, and quality assessment were independently
 conducted by members of the review team (CJP, JMG, AK, MW, LA, and JGG).
 The review team was composed of six members. The review
 team first screened titles and abstracts to identify studies that met the
 inclusion criteria. Next, the full texts of studies included during the
 title and abstract were screened using the same eligibility criteria. Each
 article was screened by two reviewers and conflicts between reviewers were
 resolved by consensus discussion with the review team.
 <strong>Data collection process & data
 items</strong> Data from each included study were
 collected by two reviewers using Covidence. The following outcomes of
 interest were extracted: focus on recruitment, retention, or both; and a
 description of the evidence-based strategies. We extracted data on study
 characteristics, including year of publication and condition of interest,
 including subtype for cancer. Additionally, we extracted characteristics
 including race and ethnicity, sex assigned at birth if applicable,
 geography (urban or rural), and role in clinical research (e.g.,
 participant, clinician (i.e., medical or research staff), community
 leader, etc.). <strong>Study risk of bias
 assessment</strong> For the quality assessment,
 we evaluated the following domains: (a) role of the researcher; (b)
 sampling method; (c) data collection method; and (d) analysis method,
 which were identified as<em> all criteria met</em> or
 <em>criteria partially met</em>. We followed the adapted
 guidelines and conceptual domains of the Critical Appraisal Skills
 Programme (CASP) quality assessment tool to assess the quality of studies.
 Two reviewers assessed the risk of bias for each included study and
 resolved disagreements by consensus discussion with the review
 team. <strong>Synthesis
 methods</strong> A thematic synthesis was
 operationalized for the data analysis, where we analyzed the findings and
 developed inductive and deductive codes using qualitative synthesis
 methodologies and established guidelines. The thematic synthesis utilized
 an iterative process grounded in qualitative thematic analysis
 methodologies. We initially developed a deductive coding scheme, focusing
 on direct meaning and content that highlighted evidence-based strategies
 and direct quotations from study participants. The team discussed and
 created the codebook, and then each code was defined. Discrepancies or
 additional deductive codes were added and discussed by the team for
 consensus. Each study was coded independently by reviewers. Inductive
 codes were later added to describe high-level interpretation and themes.
 Both deductive and inductive codes existed in our codebook using this
 iterative process. Further analysis was conducted where strategies and
 themes were summarized into a conceptual model emphasizing key elements
 for the recruitment and retention of racial and ethnic groups historically
 underrepresented in clinical research.
description: # Recruitment and retention strategies for improving representation in
 clinical research: A meta-synthesis
 [https://doi.org/10.5061/dryad.n02v6wx79](https://doi.org/10.5061/dryad.n02v6wx79) ## Description of the data and file structure This systematic review was performed by first determining our scope of the research and defining our inclusion and exclusion criteria. Using this information, the NIH Library of Medicine performed a literature search using the following databases: PubMed (National Library of Medicine), Embase (Elsevier), CINAHL Plus (Cumulative Index to Nursing and Allied Health Literature - EBSCOhost), and Web of Science Core Collection (Clarivate Analytics). The literature identified in the search was imported into the Covidence systematic review software, where the data were screened to identify literature that fit the inclusion criteria. Data from each included study were collected by two reviewers using Covidence. The following outcomes of interest were extracted: focus on recruitment, retention, or both; and a description of the evidence-based strategies. The data was extracted on study characteristics. A thematic synthesis was operationalized for the data analysis, where the team analyzed the findings and developed inductive and deductive codes using qualitative synthesis methodologies and established guidelines. ### Files and variables #### File: All\_Excluded\_and\_Included\_Studies.xlsx **Description:** This contains a comprehensive list of all literature (4756 studies) that was identified in the initial search for this study by Peters et al. Using the defined search strategy, this list encompasses all the studies initially identified across the following databases: PubMed (National Library of Medicine), Embase (Elsevier), CINAHL Plus (Cumulative Index to Nursing and Allied Health Literature - EBSCOhost), and Web of Science Core Collection (Clarivate Analytics). The table lists the title of the literature, authors, publication date, journal volume, issue, pages, digital object identifier (DOI), and the reason for exclusion. The literature screened out during the title and abstract screening (3842 studies) is in the table. The literature excluded during the full text review (887 studies) is in the table. The literature included in the systematic review (27 studies) is in the table. Any missing values in the table are listed as blank cells. #### File: All\_Data\_Extracted\_for\_Systematic\_Review\.docx **Description:** This table includes all the data extracted from the primary research sources that were included in this systematic review. The following outcomes of interest were extracted: focus on recruitment, retention, or both; and a description of the evidence-based strategies. The table also includes the data extracted based on study characteristics including race/ethnicity, condition of interest, sex assigned at birth where noted, role in clinical research (e.g., participant, clinician (i.e. medical or research staff), community leader, etc.), geography of study (urban or rural), the name of the data extractors, date of data extraction, and the confirmation that the study was eligible for inclusion. #### File: Quality\_Review\.docx **Description:** This table includes the completed quality assessment for each study. The table lists all the studies that were included in the systematic review and the questions that were asked to assess whether the study partially met or fully met all criteria. ## Code/software Covidence Systematic Review Software [https://www.covidence.org/](https://www.covidence.org/) ## Access information Other publicly accessible locations of the data: * PubMed (National Library of Medicine) - [https://pubmed.ncbi.nlm.nih.gov/](https://pubmed.ncbi.nlm.nih.gov/) * Embase (Elsevier) - [https://www.embase.com/search/quick](https://www.embase.com/search/quick) * CINAHL Plus (Cumulative Index to Nursing and Allied Health Literature - EBSCOhost) - [https://www.ebsco.com/products/research-databases/cinahl-database](https://www.ebsco.com/products/research-databases/cinahl-database) * Web of Science Core Collection (Clarivate Analytics) - [https://clarivate.com/academia-government/scientific-and-academic-research/research-discovery-and-referencing/web-of-science/web-of-science-core-collection/](https://clarivate.com/academia-government/scientific-and-academic-research/research-discovery-and-referencing/web-of-science/web-of-science-core-collection/) Data was derived from the following sources: N/A