1. aSchool of Public Health, Bengbu Medical College, Bengbu, China
2. bSchool of Public Health, Wannan Medical College, Wuhu, China
3. cCentre for Health Management and Policy Research, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
4. dNHC Key Laboratory of Health Economics and Policy Research, Shandong University, Jinan, China