Objectives Systematic review of studies evaluating evidence-based health information (EBHI) and decision aids (DAs) in terms of the extent to which inequity-producing factors have been considered and how these factors affect access to health-related information and informed decision-making. Study design Systematic review of randomised controlled trials. Methods Systematic searches were performed in the Cochrane Library, PubMed, Embase, PsycINFO, CINAHL, ERIC and PSYNDEX from inception to May 2023 to identify evaluation studies of EBHI and DAs that take into account factors associated with unequal opportunities as defined by PROGRESS Plus. Information on the effect of these factors was extracted and analysed in terms of outcomes relevant to the decision-making process. Results Few studies have examined the impact of EBHI/DAs on outcomes relevant to decision-making with respect to inequity-producing factors. In our final synthesis,12 studies were included. A positive association between the effectiveness of the intervention and the disadvantage status could be found twice and a negative association in three studies. Overall, most of the studies found no difference in knowledge gain, decision conflict and shared decision-making (SDM) between those advantaged and disadvantaged in terms of ethnicity, gender, education, age, income, health literacy, numeracy or socioeconomic status (SES). However, few trials examined this effect and the effect was considered solely in subgroup analyses that were probably underpowered, so asymmetries between these groups may not have been detected in the existing designs. Conclusion EBHI and DAs have been shown to be effective in promoting decision-making and thus in improving health care. To improve health care equitably, greater attention needs to be paid to methodological requirements in evaluations to fully capture potential differences in access to health-related information between individuals or in populations within the target groups of EBHI/DAs. PROSPERO registration: CRD42018103456 Key words: Equity, decision aids, decision-making, informed choice, evidence-based

The authors have declared no competing interest.

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