Long-run measurement of income-related inequalities in health care under universal coverage: evidence from longitudinal analysis in Korea

Background Many countries have sought to promote well-being for their entire populations through the implementation of universal health coverage (UHC). To identify the extent to which UHC has been attained, it is necessary to evaluate equity of access to use of needed care and the cost burden of health services for the country’s entire population. This study considers income-related inequalities in health care utilization and spending in a long-term perspective for the case of the Republic of Korea. Methods Exploiting longitudinal data from a nationally representative health survey from 2008 to 2018, this study investigates how income-related inequalities in health care in Korea have varied over time and examines the extent to which need and non-need factors contribute those inequalities, using an in‐depth decomposition analysis, allowing for heterogeneous responses across income groups. Results The empirical results show that overall health care utilization is disproportionately concentrated among the poor over both the short and long run. Income-group differences and non-need determinants, such as marital status and private health insurance, make larger pro-poor contributions to inequality in inpatient care use, while chronic disease prevalence greatly pushes outpatient care utilization in a pro-poor direction. The results regarding inpatient care expenses indicate a similar pattern of pro-poor bias. Long-run inequality favors the better-off in terms of outpatient care expenses, where the contribution of income-group differences has the largest impact. Conclusion My findings suggest that it is important for health care policy in Korea to focus on improvements in the health status and well-being of low-income groups, as poor people are likely to be in poorer health. Non-need contributors could worsen pro-poor inequalities if the economic disparity across households were to increase due to the demographic transition. Higher spending on inpatient care may be a heavier financial burden for low-income people. Additional supportive measures should be provided to prevent them from suffering economic hardship. By contrast, people in high-income groups may spend most on costly services in outpatient care, including uninsured services, with the help of private health insurance. Nevertheless, the expansion of income disparity should be alleviated even from a health care policy perspective.