1. Gastrointestinal and Liver Diseases Division, Keck Medicine of University of Southern California, Los Angeles, California, USA;
2. Division of Gastroenterology and Hepatology, University of Michigan, Ann Arbor, Michigan, USA;
3. Departments of Biostatistics, and Epidemiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA;
4. Liver Diseases Branch, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, USA;
5. Baylor University Medical Center, Dallas, Texas, USA;
6. Division of Gastroenterology, University of North Carolina, Chapel Hill, North Carolina, USA;
7. Toronto Centre for Liver Disease, University of Toronto, Toronto, Ontario, Canada;
8. Department of Medicine, University of California San Francisco, San Francisco, California, USA;
9. Liver Center, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard University, Boston, Massachusetts, USA;
10. Section of Hepatology, Virginia Commonwealth University, Richmond, Virginia, USA;
11. Department of Medicine, University of St. Louis, St. Louis, Missouri, USA;
12. Washington University School of Medicine and John Cochran VA Medical Center, St. Louis, Missouri, USA;
13. San Francisco Center for Liver Disease, California Pacific Medical & Research Institute, San Francisco, California, USA;
14. Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA;
15. Department of Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.