Impact of medical resources in residential area on unmet healthcare needs: Findings from a multi-level analysis of Korean nationwide data.

Purpose: This study aimed to examine whether sufficient medical resources in residential areas influence individuals' unmet healthcare needs in South Korea, where overpopulation is of concern. Methods: Two publicly available datasets were utilized: The Korean Community Health Survey at the individual-level and the Korean medical utilization statistics at the regional-level. It included 176,378 individuals. To address the clustered nature of the regional-level data, a multi-level framework was applied, containing individual-level data, incorporating demographic details and health information. Results: Individuals living in small cities and rural areas with sufficient medical resources were 1.26 times more likely to experience unmet healthcare needs than those living in well-resourced metropolitan cities. Additionally, the adjusted odds ratio for unmet healthcare needs was the highest at 1.32 for those living in small cities and rural areas lacking sufficient medical resources. Stratified analyses revealed the largest disparity in unmet healthcare needs between income levels in regions with sufficient resources. In these areas, those with the lowest income were 1.77 times more likely to experience unmet healthcare than those with the highest income. Similarly, in metropolitan cities, the income-based gap in unmet healthcare needs was most pronounced, with the adjusted odds ratio for the lowest-income group being 1.66. Conclusions: Our findings demonstrate that living in small cities or rural areas with insufficient medical resources, as well as having a low income level even in an area with sufficient medical services, significantly increases individuals' unmet healthcare needs. This suggests then need for equitable distribution medical resources across regions and public health support policies that do not limit access to medical care for people with poor socioeconomic status.