J Korean Med Sci.  2025 Mar;40(8):e111. 10.3346/jkms.2025.40.e111.

Leveraging National Health Insurance Service Data for Public Health Research in Korea: Structure, Applications, and Future Directions

• Lim SJ
• Jang SI

• KMID: 2565793
• DOI: http://doi.org/10.3346/jkms.2025.40.e111

Abstract

The National Health Insurance Service (NHIS) database serves as a crucial resource for public health research in Korea. As a comprehensive dataset within the single-payer healthcare system, NHIS data provides longitudinal insights into healthcare utilization, disease prevalence, and health outcomes. This review article explores the structure, characteristics, and applications of NHIS data, emphasizing its role in epidemiological studies, health policy evaluations, and clinical research. We discuss key methodological considerations, including data access procedures, outcome measures, and strategies to mitigate bias. Additionally, we highlight future directions, such as integrating NHIS data with other national health datasets and utilizing artificial intelligence for predictive analytics. By leveraging the NHIS database, researchers can enhance evidence-based policymaking and improve public health outcomes in Korea.

Keyword

National Health Insurance Service; Public Health Research; Epidemiology; Big Data; Health Policy; Healthcare Utilization

Figure

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  Fig. 1 Data generation and operational process of the NHIS.NHIS = National Health Insurance Service, MOHW = Ministry of Health and Welfare, HIRA = Health Insurance Review and Assessment Service.

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  Fig. 2 Timeline of integration for health insurance cooperatives (redrawn from the World Bank material).MIC = Medical Insurance Cooperative, KMIC = Korea Medical Insurance Corporation.

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