ABSTRACT
Background@#On October 1, 2017, a new coinsurance reduction policy for children under 15 was introduced to minimize the lack of inpatient medical services for economic reasons and secure children’s access to medical care. @*Methods@#This study analyzes the effect of this coinsurance reduction policy on healthcare utilization using data from the National Health Insurance Service-National Sample Cohort between 2015 and 2019. Groups were classified by 3 case groups and a control group according to age. The dependent variables were inpatient cost, admission, length of hospitalization, outpatient cost and visit, and total cost. The difference-in-differences method was used to examine changes in healthcare utilization among the case and control groups after policy implementation. @*Results@#Children of the age group 1–5 exhibited an increase in inpatient services and a decrease in outpatient services. There was a 16.17% increase in inpatient cost, 8.55% increase in inpatient admission, 10.67% increase in inpatient length of hospitalization, −9.14% decline in outpatient cost, and −6.79% decline in outpatient visits. Regarding children in the age groups of 6–10 and 11–15, the effect of the policy was inconclusive. @*Conclusion@#The reduction in coinsurance rate policy in hospitalization among children has increased inpatient services and reduced outpatient services for 1–5-year-olds—a substitute effect was observed in this group. There is need for further research to examine the longterm effects of the coinsurance reduction policy.