The impact of urban–rural medical insurance integration on medical impoverishment: evidence from China

BACKGROUND: Financial protection is a key dimension of Universal Health Coverage (UHC), and social medical insurance is an effective measure to provide financial protection. The aim of this study is to examine the impact of urban–rural medical insurance integration on medical impoverishment in China. METHODS: We collected the time of integration policy in 337 prefecture-level cities across China, combined with the longitudinal database of China Labor-force Dynamics Survey (CLDS) from 2012–2016, and used a difference-in-differences (DID) method with multiple time periods at the city level to study the effect of urban–rural medical insurance integration on the medical impoverishment. Besides, to explore the heterogeneity of policy effects across populations, we conducted subgroup analyses based on respondents' age, household registration, and whether they were rural–urban migrants. FINDINGS: A total of 8,397 samples were included in the study. The integration policy has significantly reduced the incidence of medical impoverishment (average treatment effect on the treated (ATT) = − 0.055, p < 0.05). Subgroup analysis showed that the impacts on medical impoverishment varied by age group, and the integration policy has more effect on older people than on younger people (ATT for age 15–34 = − 0.018, p > 0.05; ATT for age 35–54 = − 0.042, p < 0.05; ATT for age 55–64 = − 0.163, p < 0.01). Moreover, the impacts also varied by household registration. The integration policy has a more significant impact on rural residents (ATT for rural = − 0.067, p < 0.05) compared to urban residents (ATT for urban = − 0.007, p > 0.05). Additionally, the policy has a bigger influence on rural–urban migrants (ATT for rural–urban migrated = − 0.086, p < 0.05) than on those who have not migrated (ATT for rural–urban unmigrated = − 0.071, p < 0.05). CONCLUSION: China's policy of integrating urban–rural medical insurance has been successful in reducing medical impoverishment, especially for older age, rural, and rural–urban migrated people. It can be speculated that the integrating policy may be adapted to other similar settings in developing countries to reduce medical impoverishment. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12939-023-02063-6.