1. Department of Medicine, Division of Gastroenterology and Hepatology, University of California San Diego, La Jolla, California, USA;
2. Department of Biostatistics and Informatics, Colorado School of Public Health, University of Colorado-Anschutz Medical Campus, Aurora, Colorado, USA;
3. Department of Medicine, Division of Gastroenterology and Hepatology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA;
4. Department of Medicine, Division of Gastroenterology, Hepatology and Endoscopy, Brigham and Women's Hospital, Boston, Massachusetts, USA;
5. Harvard Medical School, Boston, Massachusetts, USA;
6. Department of Medicine, Division of Gastroenterology and Hepatology, Tzu Chi University, Hualien County, Taiwan;
7. Department of Medicine, Division of Gastroenterology, Washington University, St. Louis, Missouri, USA.