1. Department of Healthcare Epidemiology, School of Public Health in the Graduate School of Medicine Kyoto University Kyoto Japan
2. Section of Clinical Epidemiology, Department of Community Medicine, Graduate School of Medicine Kyoto University Kyoto Japan
3. Department of Gastroenterology Dokkyo Medical University Tochigi Japan
4. Department of Gastroenterology and Hepatology Kyorin University School of Medicine Tokyo Japan
5. Center for Advanced IBD Research and Treatment Kitasato University Kitasato Institute Hospital Tokyo Japan
6. Division of Gastroenterology and Hepatology, Department of Internal Medicine Toho University Sakura Medical Center Chiba Japan
7. Department of Gastroenterology Aichi Medical University School of Medicine Aichi Japan
8. Department of Surgery Kurume Coloproctology Center Fukuoka Japan
9. Department of Gastroenterology and Metabolism Nagoya City University Graduate School of Medical Sciences Aichi Japan
10. Division of Gastroenterology and Hepatology, Department of Internal Medicine The Jikei University School of Medicine Tokyo Japan
11. Department of gastroenterology Fujita Health University Aichi Japan
12. Division of Gastroenterology and Hepatology, Department of Internal Medicine Keio University School of Medicine Tokyo Japan
13. Department of Gastroenterology Kure Kyosai Hospital Hiroshima Japan
14. Gastroenterology and Endoscopy, Division of Metabolism and Biosystemic Science, Gastroenterology, and Hematology/Oncology Asahikawa Medical University Hokkaido Japan
15. Department of Gastroenterology and Hepatology Tokyo Medical University Tokyo Japan
16. Division of Gastroenterology Shiga University of Medical Science Shiga Japan