Income-related equity in inpatient care utilization and unmet needs between 2013 and 2018 in Tibet, China

Providing equitable access to health care for all populations is an important sustainable development goal. China has made significant progress in achieving equity in healthcare utilization. However, research on equity in healthcare utilization in Tibet is sparse. This study aims to evaluate changes in income-related inequity in inpatient care utilization and unmet needs between 2013 and 2018 among the Tibetan population and identify the inequity source. Data for this cross-sectional study were obtained from the fifth and sixth waves of the National Health Services Survey in 2013 and 2018. After excluding observations with missing values for key variables, 11,092 and 10,397 respondents were included in this study, respectively. The outcome variables of interest were inpatient service utilization and unmet hospitalization needs. The concentration index and horizontal inequity index (HI) were used to assess income-related inequity. Non-linear decompositions were performed to identify the main contributors to inequity. In the decomposition method, need variables included sex, age, chronic diseases, and the EuroQol-Visual Analog Scale; non-need variables consisted of income, education, employment status, marital status, and health insurance schemes. The probability of inpatient care utilization increased from 6.40% in 2013 to 8.50% in 2018. The HI for inpatient care utilization was 0.19 (P