1. Department of Medical Insurance, School of Public Health, Southeast University, Nanjing, China
2. Guangdong Provincial Geriatrics Institute, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
3. School of Health and Wellbeing, University of Southern Queensland, Ipswich, Queensland, Australia
4. Department of Epidemiology and Biostatistics, School of Public Health, Southeast University, Nanjing, China