OBJECTIVES: Distributional cost-effectiveness analysis (DCEA) evaluates healthcare interventions by considering both their cost-effectiveness and their impacts on health inequality. A recently developed method, it is unfamiliar to many which hinders its widespread use. This study aimed to characterize all previously published DCEAs to provide learnings for wider use.

METHODS: A systematic literature review was performed to identify all DCEAs published between 2014 and 2024 using Embase and PubMed databases. Inclusion criteria included studies classified as DCEA or those incorporating equity information across various population distributions. Extracted information included DCEA structure, geography and data assumptions.

RESULTS: Twenty-eight studies met the inclusion criteria. The number of published studies increased over time from 1 in 2014 to 7 in 2023. 16 DCEAs were conducted in aggregate form and 12 were full DCEAs.

DCEAs were conducted across many disease areas including cancer, infectious disease and cardiovascular disease. Studies used several different country perspectives, with a notable concentration of studies looking at the UK (37%). Only studies in the UK and US used aggregate approaches. Various domains of equity were investigated including Index of Multiple Deprivation (all UK studies), socioeconomic position or Social Vulnerability Index (Australia and US), race and ethnicity (US), income or wealth-related indices (African countries). Other factors such as rural vs urban settings and age were also included across both high- and low-income country settings. Most studies (90%) showed that interventions were equity-improving. Data limitations frequently led to reliance on assumptions.

CONCLUSIONS: This systematic review highlights the growing interest in and application of DCEA across various disease areas, geographies and equity domains. Further research is needed to assess how data limitations are best mitigated, but given the variety of case studies identified, DCEA can already be used more widely to help to identify health interventions that can reduce health inequalities.