Can health information and decision aids decrease inequity in health care? A systematic review.

Objectives: A systematic review of studies evaluating evidence-based health information (EBHI) and patient decision aids (PtDAs) was conducted in order to ascertain the extent to which inequity-producing factors have been considered, and in how far people from different sociodemographic groups benefit equally from them in terms of informed decision-making. Design: Systematic review of randomised controlled trials (RCTs). Data sources: Systematic searches were performed in the Cochrane Library, MEDLINE, PMC, EMBASE, PsycINFO, CINAHL, ERIC and PSYNDEX from inception to May 2023. Eligibility criteria: RCTs of EBHI and PtDAs that take into account factors associated with unequal opportunities as defined by PROGRESS-Plus. Data extraction and synthesis: 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/PtDAs on outcomes relevant to informed 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 disadvantaged status could be found two times and a negative association in three studies. Overall, most of the studies found no difference in knowledge gain, decision conflict and shared decision-making between those advantaged and disadvantaged in terms of ethnicity, gender, education, age, income, health literacy, numeracy or socioeconomic status. 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 PtDAs have been shown to be effective in promoting decision-making and thus in improving healthcare. To improve healthcare 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/PtDAs. PROSPERO registration number: CRD42018103456.