Abstract: Background Previous studies have not investigated the association between medical insurance and instrumental activity of daily living (IADL) disability. To fulfll this research gap, this study aims to explore the associationbetween Urban and Rural Resident Basic Medical Insurance (URRBMI) and IADL disability among middle-agedand older adults in China.Methods The data of this study were sourced from the 2018 wave of China Health and Retirement LongitudinalStudy (CHARLS). Logit regression models were used to analyze the association between URRBMI and odds of suferingfrom IADL disability. Furthermore, we used IV-Probit regression model to address the potential endogeneity problem.Moreover, propensity score matching and generalized random forest model were employed to conduct robustnesschecks.Results The logit regression results reveal that URRBMI participation was signifcantly related to reduced odds of suffering from IADL disability by 39.86% after adjusting for the control variables (p<0.01). The results of IV-Probit estimation show that URRBMI was an exogenous variable. Further robustness checks reported similar estimation results.The results of heterogeneity analysis reveal that URRBMI produced a statistically stronger efect on IADL disabilityfor the older adults (OR=0.5815, p<0.01) when compared with the middle-aged adults (OR=0.5690, p<0.05). Theresults of impact channel analysis indicate that physical exercise was a channel involving the efect of URRBMI on IADLdisability.Conclusion This study fnds that the middle-aged and older adults who were covered by URRBMI had a reducedpossibility of sufering from IADL disability when compared with those without URRBMI. Furthermore, it is foundthat URRBMI produced a statistically stronger efect on IADL disability for the older adults when comparedwith the middle-aged adults. Moreover, we obtain evidence indicating that physical exercise was a channel involvingthe efect of URRBMI on IADL disability

Keyword: Urban and Rural Resident Basic Medical Insurance, Instrumental activity of daily living disability, Middleaged and older adults, China Health and Retirement Longitudinal Study, China