상복부초음파검사 급여확대에 따른 의료이용의 변화: 이중차이 혼합효과모형 추정방법을 이용하여

Abstract

Background: Korea has gradually expanded the coverage of medical care services in its national health insurance system. On April 1, 2018, it implemented a policy that expanded the coverage for an ultrasonography in the upper abdomen. In this study, we aimed to investigate the effect of the policy on the utilization of the ultrasonography in the upper abdomen in tertiary care hospitals. Methods: Using the dataset of the Health Insurance Review and Assessment Service, we explored changes in the utilization of the ultrasonography in the upper abdomen in tertiary care hospitals from July 1, 2017 to November 30, 2018 through the difference-in-difference (DID) mixed-effects-model method. Facility factor, equipment factor and personnel factors, type of hospital, the total amount of medical care expenses, and geographic region were considered as control variables. Results: On average, the utilization of the ultrasonography in the upper abdomen increased by 228% after the coverage expansion policy. However, the results of DID mixed-effects-model method analysis showed that the utilization increased by 73%. As for the number of beds, the utilization was higher with a group of 844-930, 931-1,217, and 1,218 or greater compared with a group of 843 or fewer, while the utilization of the number of ultrasonic devices was lower with a group of 45-49 compared with a group of 44 or fewer. The utilization decreased with the number of interns and the number of nurse assistants. Besides, relative to Seoul, the utilization was lower in the other metro-cities and provinces. Conclusion: The coverage expansion policy in the national health insurance system increased service utilization among people. Future research needs to investigate the degree to which such coverage expansion policy reduces the unmet medical care needs among the deprived in Korea.