1. Department of Health Services Research, Graduate School of Medicine The University of Tokyo Tokyo Japan
2. Department of Clinical Data Management and Research, Clinical Research Center National Hospital Organization Headquarters Tokyo Japan
3. Department of Emergency and Critical Care Medicine National Hospital Organization Mito Medical Center Ibarakimachi Japan
4. Department of Clinical Epidemiology and Health Economics, School of Public Health The University of Tokyo Tokyo Japan
5. National Hospital Organization Kyushu Medical Center Fukuoka Japan
6. National Hospital Organization Nagasaki Medical Center Omura Japan
7. National Hospital Organization Minami Wakayama Medical Center Tanabe Japan
8. National Hospital Organization Asahikawa Medical Center Asahikawa Japan
9. Department of Health Policy and Informatics Tokyo Medical and Dental University Graduate School Tokyo Japan