Study shows income gaps drive disparities in universal healthcare access

Higher levels of human development are associated with better universal health coverage worldwide, and disparities in coverage between income groups are generally larger than disparities between world regions. Those are two of the conclusions of a new study published this week in the open-access journal PLOS Global Public Health by Akira Hayasaka of Yokohama City University, Japan, Yasuhiro Nakanishi of the National Institute of Public Health, Japan, and colleagues.

Universal health coverage (UHC) is a core target of the Sustainable Development Goals, tracked using the UHC Service Coverage Index (SCI), a composite score built from four domains: reproductive, maternal, newborn, and child health; infectious diseases; noncommunicable diseases; and service capacity and access. UHC and human development are closely linked because of how greater access to health care leads to better health outcomes in general (due to preventative care, screenings, vaccinations, etc). However, how this relationship varies across coverage domains, income groups, and world regions over time has not been systematically examined.

In the new study, researchers conducted a retrospective, country-level longitudinal analysis using 7 different years of publicly available World Health Organization and United Nations data spanning 2000-2021. The dataset allowed them to compare the UHC Service Coverage Index and its four sub-indices with the Human Development Index (HDI) and its components across World Bank income groups and WHO regions.

After adjusting for other variables, low-income countries had significantly lower UHC coverage than high-income countries (21% lower overall), with the largest gaps in the infectious disease domain (31% lower). These income-group disparities were generally larger than differences between WHO regions. A 0.1-unit increase in HDI was associated with a 6.8-point higher overall UHC score (95% CI 5.6–8.1), with the strongest association for service capacity and access (11.7 points) and the weakest for noncommunicable diseases (2.2 points).

The study measured countries, not individuals, so it could not capture inequalities in coverage within countries, and changes to the index's underlying indicators over time limit comparisons across different report editions. However, the researchers concluded that higher levels of human development were associated with better UHC coverage, and that persistent disparities exist across income groups. 

"These findings may help policymakers interpret the UHC SCI and its sub-indices in the context of their country's broader development trajectory," the authors say.

The authors add: "Higher levels of human development were associated with better health service coverage, although the strength of this relationship differed across domains. We believe that our findings, which demonstrate that development in sectors beyond healthcare is associated with access to healthcare services, can provide valuable insights into strategies for creating a healthier world."