1. Department of Medicine, Division of Gastroenterology, Washington University School of Medicine, Saint Louis, MO, USA
2. Department of Medicine, Division of Digestive and Liver Diseases, Columbia University Medical Center, New York, NY, USA
3. Connecticut Gastroenterology, Bristol, CT, USA
4. Department of Gastroenterology and Hepatology, Amsterdam University Medical Centers, Amsterdam, The Netherlands
5. Department of Medicine, Division of Gastroenterology and Hepatology, Mayo Clinic Rochester, Rochester, MN, USA