Methods for studying health disparities in U.S. nursing homes: a scoping review

Abstract Background Health disparities exist across healthcare settings, including nursing homes, contributing to preventable differences in care quality. Health disparities are a global issue, yet most studies on nursing home health disparities have been conducted in the United States. In this scoping review, our objective was to synthesize methods used in U.S. nursing home disparities research to gain insights to inform similar research in other countries. Specifically, we summarized different approaches for conceptualizing and measuring health disparities, available data sources, study designs, and analytic strategies. Methods We employed two parallel search strategies across five databases, targeting specific aspects of health disparities and broader concepts. Study selection was conducted independently by two reviewers. Using a numerical and analytic approach, we categorized and summarized the results. Results The search yielded 6,817 records, with 82 unique studies meeting the inclusion criteria. All studies used quantitative methods, with only two incorporating mixed methods. Most were observational cross-sectional studies (n = 60), while 21 were longitudinal studies, and 1 was a randomized controlled trial. Most studies used administrative data (n = 62). The majority (n = 65) measured differences in health outcomes across nursing homes. A significant number of studies (n = 71) focused on racial and/or ethnic health disparities, and a few studied clinical conditions (n = 7), rural–urban location of the nursing home (n = 4), socioeconomic factors (n = 4), age (n = 1), and sex (n = 1) as characteristics to measure disparity. Outcomes were grouped into five domains: 1) Quality of care measures (n = 54), 2) Infection and infection prevention (n = 22), 3) Transitions and acute care utilization (n = 19), 4) Behavioral and mental health (n = 18), and 5) Palliative care, end-of-life and death (n = 13). Across the five domains, the most prevalent outcome category studied was ‘Hospitalization and emergency room use’ (n = 15). Conclusion This review highlights key issues for future research on health disparities in nursing homes, including the need to: 1) clarify concepts of health disparities and health equity; 2) move beyond mere descriptions of disparities to identify underlying factors contributing to those disparities; 3) broaden examination of disparities beyond a single axis such as race or sex; 4) integrate more qualitative data to capture nuances that cannot be measured from quantitative data; and 5) specify whether within or across nursing home differences are studied.