1. Department of Health Policy and Planning, Graduate School of Medicine, the University of Tokyo, Tokyo, Japan
2. Institute of Social Medicine and Health Services Management, School of Public Health, Shandong University, Jinan City, Shandong Province, China,
3. Institute of Social Medicine and Health Services Management, School of Public Health, Shandong University, Jinan City, Shandong Province, China
4. The University of Tokyo Hospital, Tokyo, Japan