1. Division of Gastroenterology; University of Michigan; Ann Arbor MI USA
2. Data Coordinating Center; Johns Hopkins University; Baltimore MD USA
3. Section of Gastroenterology; Temple University; Philadelphia PA USA
4. Section of Gastroenterology; Johns Hopkins University; Baltimore MD USA
5. Section on Gastroenterology; Wake Forest University; Winston Salem NC USA
6. Division of Gastroenterology; University of Louisville; Louisville KY USA
7. Section of Gastroenterology; Texas Tech University; El Paso TX USA
8. Division of Gastroenterology; Stanford University; Palo Alto CA USA
9. Division of Gastroenterology; California Pacific Medical Center; San Francisco CA USA
10. Section of Gastroenterology; Mayo Clinic; Rochester MN USA
11. Endocrinology Section; MetroHealth Medical Center; Cleveland OH USA
12. Section of Gastroenterology; Johns Hopkins University Data Coordinating Center; Baltimore MD USA
13. National Institute of Diabetes and Digestive and Kidney Diseases; Bethesda MD USA