1. Division of General Medicine, Department of Medicine, Taipei Veterans General Hospital, Taipei 112, Taiwan
2. Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei 112, Taiwan
3. Division of Gastroenterology, Department of Medicine, Taipei Veterans General Hospital, Taipei 112, Taiwan
4. Department of Medical Affair and Planning, Taipei Veterans General Hospital, Taipei 112, Taiwan
5. Department of Medical Research, Taipei Veterans General Hospital, Taipei 112, Taiwan
6. Division of Gastroenterology, Department of Medicine, Cheng-Hsin General Hospital, Taipei 112, Taiwan