The purpose of this study is to explore the client service experience of medicaid case managers in Korea and prepare health protection measures. The research method was in-depth interviews, and data was collected twice in total from 04 September to 06 September, 2023. The study participants were five medicaid care managers belonging to cities, counties, and districts across the country. As a result of this study, participants experienced problem behaviors such as unreasonable demands, verbal abuse and assault, a threatening environment, a passive attitude toward expressing emotions, and a defensive attitude when performing work. In addition, the participants appeared to be unaware of the organization’s management policy, the absence of a healing program for health disorders, and the follow-up management system to resolve client problem behavior. In conclusion, the organization must establish a safety and health management policy, establish a grievance handling committee, conduct safety and health education, investigate job stress and prepare countermeasures, prepare follow-up measures to protect health, and prepare a job stress relief program.

South Korea has experienced rapid economic development since the 1960s. However, pronounced regional disparities have concurrently emerged. Amid the escalating regional inequalities and persistent demographic challenges characterized by low fertility rates, regional decline has become a pressing issue. Therefore, the feasibility of expanding transportation networks as a countermeasure to regional decline has been proposed. This study utilizes the synthetic control method and spatial difference-in-differences methodologies to assess the impact of the 2017 opening of Seoul–Yangyang Expressway on economic development and population inflow within Hongcheon-gun, Inje-gun, and Yangyang-gun. The purpose of this study is to evaluate the effectiveness of highway development as a policy instrument to mitigate regional decline. Findings from the synthetic control method analysis suggest a positive impact of the opening of the expressway on Hongcheon-gun’s Gross Regional Domestic Product (GRDP) in 2018, as well as Yangyang-gun’s net migration rates from 2017 to 2019. Conversely, the spatial difference-in-differences analysis, designed to identify spillover effects, reveals negative impacts of the highway on the GRDP and net migration rates of adjacent regions. Consequently, although targeted transportation infrastructure development in key non Seoul Metropolitan cities may contribute to ameliorating regional imbalances, results indicate that such measures alone are unlikely to suffice in attracting population to small- and medium-sized cities outside the Seoul Metropolitan Area.