- Robust standard error in brackets, * * * P < 0.01, * * P < 0.05, * P < 0.1. Here, the explained variables outpatient reimbursement expenses and inpatient reimbursement expenses are logarithmicized. The instrumental variable is the geographical region, which can comprehensively reflect the social and economic environment and other factors. The results of first-stage test confirms its effectiveness. The results of individual health variables ADL, serious diseases, self-rated health, degree of depression, and physical pain as well as age, marital status education, gender, and other variables reflecting individual characteristics are not listed
Archives of Public Health