1. Department of Gastroenterology, National Hospital Organization Kure Medical Center and Chugoku Cancer Center, Kure, Japan
2. Department of Gastroenterology and Hepatology, National Hospital Organization Osaka National Hospital, Osaka, Japan
3. Department of Gastroenterology, National Hospital Organization Fukuyama Medical Center, Fukuyama, Japan
4. Department of Gastroenterology, National Hospital Organization Nagoya Medical Center, Nagoya, Japan
5. Department of Gastroenterology, National Hospital Organization Takasaki General Medical Center, Takasaki, Japan
6. Department of Gastroenterology, National Hospital Organization Kyoto Medical Center, Kyoto, Japan
7. Department of Gastroenterology, National Hospital Organization Kanazawa Medical Center, Kanazawa, Japan
8. Department of Gastroenterology, National Hospital Organization Okayama Medical Center, Okayama, Japan
9. Department of Gastroenterology, National Hospital Organization Saitama National Hospital, Saitama, Japan
10. Department of Gastroenterology, National Hospital Organization Mie Chuo Medical Center, Tsu, Japan
11. Department of Gastroenterology, Clinical Research Institute, National Hospital Organization Kyushu Medical Center, Fukuoka, Japan