Health Policy Manag.  2020 Sep;30(3):326-334. 10.4332/KJHPA.2020.30.3.326.

Effect of Coverage Expansion Policy for an Ultrasonography in the Upper Abdomen on Its Utilization: A Difference-in-Difference Mixed-Effects Model Analysis

• Son Y
• Lee Y
• Nam CM
• Kim GR
• Chung W

• KMID: 2507301
• DOI: http://doi.org/10.4332/KJHPA.2020.30.3.326

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.

Keyword

Health insurance coverage expansion; Upper abdomen; Uultrasonography; Difference-in-difference; Mixed model; Republic of Korea