A toolkit for capturing a representative and equitable sample in health research

Research participants often do not represent the general population. Systematic exclusion of particular groups from research limits the generalizability of research findings and perpetuates health inequalities. Groups considered underserved by research include those whose inclusion is lower than expected based on population estimates, those with a high healthcare burden but limited research participation opportunities and those whose healthcare engagement is less than others. The REP-EQUITY toolkit guides representative and equitable inclusion in research. The toolkit was developed through a methodological systematic review and synthesis and finalized in a consensus workshop with 24 participants. The REP-EQUITY toolkit describes seven steps for investigators to consider in facilitating representative and equitable sample selection. This includes clearly defining (1) the relevant underserved groups, (2) the aims relating to equity and representativeness, (3) the sample proportion of individuals with characteristics associated with being underserved by research, (4) the recruitment goals, (5) the strategies by which external factors will be managed, (6) the methods by which representation in the final sample will be evaluated and (7) the legacy of having used the toolkit. Using the REP-EQUITY toolkit could promote trust between communities and research institutions, increase diverse participation in research and improve the generalizability of health research. National Institute for Health and Care Research PROSPERO identifier: CRD42022355391.