1. Department of Gastroenterology, Tokyo Metropolitan Bokutoh Hospital, Tokyo, Japan
2. Department of Gastroenterological Endoscopy, Tokyo Medical University, Tokyo, Japan
3. Department of Gastroenterology and Hepatology, National Center for Global Health and Medicine, Tokyo, Japan
4. Department of Gastroenterology and Hepatology, Kitano Hospital, Tazuke Kofukai Medical Research Institute, Osaka, Japan
5. Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
6. Department of Gastroenterology, Nippon Medical School, Graduate School of Medicine, Tokyo, Japan
7. Department of Gastroenterology, St Luke's International University, Tokyo, Japan
8. Department of Gastroenterology, Hiroshima City Asa Citizens Hospital, Hiroshima, Japan
9. Department of Gastroenterology, Saga Medical Center Koseikan, Saga, Japan
10. Division of Gastroenterology and Hepatology, Department of Internal Medicine, St. Marianna University School of Medicine, Kanagawa, Japan
11. Department of Gastroenterology and Hepatology, Center for Digestive and Liver Diseases, Nara City Hospital, Nara, Japan
12. Department of Gastroenterology, Tokyo Shinagawa Hospital, Tokyo, Japan
13. Departmment of Endoscopy, Nagoya University Hospital, Aichi, Japan
14. Department of Gastroenterology, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
15. Department of Gastroenterology, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital, Tokyo, Japan
16. Department of Gastroenterology, Oita University, Oita, Japan
17. Department of Gastroenterology, Fukuoka University Chikushi Hospital, Fukuoka, Japan
18. Department of Gastroenterology, Chiba Hokusoh Hospital, Nippon Medical School, Inba-gun, Japan
19. Department of Gastroenterology, Japanese Red Cross Shizuoka Hospital, Shizuoka, Japan
20. Division of Endoscopy and Ultrasonography, Department of Clinical Pathology and Laboratory Medicine, Kawasaki Medical School General Medical Center, Okayama, Japan
21. Division of Gastroenterology, Graduate school of Medical and Dental Sciences, Niigata University, Niigata, Japan
22. Department of Gastroenterology and Hepatology, Center for Digestive Disease and Division of Endoscopy, University of Miyazaki Hospital, Miyazaki, Japan
23. Division of Endoscopic Center, University of Tsukuba Hospital, Ibaraki, Japan
24. Department of Gastroenterology, University of Tsukuba, Ibaraki, Japan
25. Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan