실손형의료보험 가입이 공급자 유인수요에 미치는 이질적 처리효과 분석

This study examines the causal effects of private health insurance(PHI) on medical utilization and supplier-induced demand(SID), with a particular focus on the heterogeneous effects of the fourth-generation indemnity insurance introduced in 2021. Using data from the Korea Health Panel(2019-2023), we apply the Callaway and Sant‘Anna(2021) CSDID estimator to address the ‘bad comparison‘ bias inherent in traditional Difference-in-Differences models. The empirical results reveal distinct heterogeneity across enrollment cohorts. While traditional models found no significant effects, the CSDID approach identified significant ‘advantageous selection‘ among fourth-generation indemnity insurance enrollees(2022 cohort), who exhibited lower medical utilization prior to enrollment. Furthermore, the short-term moral hazard in high-cost diagnostic scans observed among third-generation indemnity insurance enrollees disappeared among fourth-generation enrollees. These findings suggest that the structural reforms introduced in the fourth-generation indemnity insurance program, such as premium surcharges, effectively attract low-risk enrollees and curb over-utilization.