1 Center for Database Research and Division of Gastroenterology, E-Da Hospital and School of Medicine for International Students, I-Shou University, Kaohsiung City, Taiwan.
2 Division of Gastroenterology, Taichung Veterans General Hospital, Taichung City and Faculty of Medicine, School of Medicine, National Yang-Ming University, Taipei City and College of Public Health and Graduate Institute of Clinical Medicine, China Medical University, Taichung City, Taiwan.