1. Department of Emergency Medicine, Yamato Tokushukai Hospital, Yamato, Kanagawa, Japan
2. Department of Diagnostic and Generalist Medicine, Dokkyo Medical University, Mibu, Tochigi, Japan
3. General Medicine Center, Shimane University Hospital, Izumo, Shimane, Japan
4. Division of General Medicine, Showa University Koto Toyosu Hospital, Tokyo, Japan
5. Department of General Medicine, Juntendo University Faculty of Medicine, Tokyo, Japan
6. Department of General Medicine, Chiba University Hospital, Chiba, Japan