The effect of extension of benefit coverage for cancer patients on health care utilization across different income groups in South Korea.

To provide financial protection against catastrophic illness, the Korean government expanded the National Health Insurance (NHI) benefit coverage for cancer patients in 2005. This paper examined whether the policy improved the income-related equality in health care utilization. This study analyzed the extent to which the policy improved income-related equality in outpatient visits, inpatient days, and inpatient and outpatient care expenditure based on triple difference estimator. Using nationwide claims data of the NHI from 2002 to 2004 and from 2006 to 2010, we compared cancer patients as a treatment group with liver disease as a control group and low-income group with the highest-income group. The results showed that the extension of NHI benefits coverage led to an increase in the utilization of outpatient services across all income groups, but with a greater increase for the low-income groups, among cancer patients. Moreover, the policy led to a less decrease in the utilization of inpatient services for the low-income group while it decreased across all income groups. Our finding suggests that the extension of NHI benefits coverage improved the income-related equality in health care utilization.