Incorporating Equity Considerations Related to Financial Protection Through Extended Cost-Effectiveness Analysis: A Systematic Review.

INTRODUCTION: Extended cost-effectiveness analysis (ECEA) incorporates financial risk protection (FRP) and distributional outcomes across socioeconomic groups. This study assessed FRP outcomes and synthesized the landscape of ECEA applications. METHODS: A systematic literature search was conducted in PubMed, Scopus, INAHTA's International HTA Database, and Tufts Medical Center's CEA Registry from January 1, 2010, to June 1, 2025. Studies were included if they report FRP outcomes such as out-of-pocket expenditure (OOPE), cases of catastrophic health expenditure (CHE), cases of poverty, value of insurance, or indirect costs. Study quality was appraised using the ECOBIAS checklist. The distribution of FRP outcomes across socioeconomic groups was assessed to determine whether benefits were pro-poor or pro-rich. RESULTS: Thirty-nine studies were included from 5,212 records screened. Most studies evaluated OOPE (n = 31), followed by CHE cases (n = 22), poverty cases (n = 16), value of insurance (n = 9), and indirect costs (n = 3). Pro-poor FRP impacts were consistently reported for tobacco taxation, immunization, and other infectious disease interventions. In contrast, some interventions, such as alcohol pricing and unhealthy diet policies, showed mixed effects depending on the FRP metric applied and the income setting. Overall, study quality was generally high, although methodological approaches and outcome definitions varied across studies. CONCLUSION: ECEA has expanded in scope and application, demonstrating its value in identifying interventions that reduce financial hardship. FRP benefits represent a critical dimension for promoting equity. Policymakers should incorporate ECEA to ensure that financial protection is evaluated alongside other values.