1. Department of Internal Medicine; Division of Gastroenterology and Hepatology; Iwate Medical University; Iwate
2. Department of Gastroenterology; Tokusyukai Kishiwada Hospital; Osaka
3. Department of Digestive Disease Information and Research and Medicine; Kurume University School of Medicine; Fukuoka
4. Department of Gastroenterology; Nippon Medical School; Tokyo
5. Department of Gastroenterology and Hepatology; Mie University Graduate School of Medicine; Mie
6. Department of Gastroenterology and Hepatology; Yamaguchi University; Yamaguchi
7. Department of Gastroenterology; Gifu University; Gifu
8. Division of Medicine and Clinical Science; Tottori University School of Medicine; Tottori
9. Social Insurance Shimonoseki Kosei Hospital; Yamaguchi; Japan