1. Division of Internal Medicine, Department of Medicine, University of Calgary, Calgary, Alberta, Canada;
2. Department of Medicine, Alberta Health Services, Calgary, Alberta, Canada;
3. Division of Gastroenterology & Hepatology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada;
4. Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada;
5. Department of Gastroenterology & Hepatology, Academic Medical Center, Amsterdam, the Netherlands;
6. Division of Gastroenterology and Hepatology, Department of Medicine, Center for Esophageal Diseases and Swallowing, Center for Gastrointestinal Biology and Disease, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA;
7. Department of Community Health Sciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.