1. Dartmouth Hitchcock Medical Center, Division of Gastroenterology and Hepatology, Lebanon, New Hampshire USA;
2. Yale School of Medicine, New Haven, Connecticut USA;
3. University of California San Diego, Division of Gastroenterology, San Diego, California USA;
4. University of Tennessee College of Medicine, Inflammatory Bowel Disease Center, Memphis, Tennessee USA;
5. Beth Israel Deaconess Medical Center, Inflammatory Bowel Disease Center, Boston, Massachusetts, USA;
6. University of Calgary, Inflammatory Bowel Disease Centre, Calgary, Alberta, Canada;
7. Amsterdam University Medical Center, Gastroenterology, Amsterdam, Netherlands;
8. Guy's and St. Thomas' Hospitals, Gastroenterology, London, United Kingdom;
9. Jefferson University, Division of Gastroenterology, Philadelphia, Pennsylvania, US;
10. Montefiore Medical Center, Division of Gastroenterology, Bronx, New York, USA;
11. The Alfred Hospital, IBD Unit, Melbourne, Victoria, Australia;
12. Cedars-Sinai Medical Center, Inflammatory Bowel Disease Center, Los Angeles, California USA.