1. Division of Gastroenterology and Hepatology University of Pennsylvania Perelman School of Medicine Philadelphia PA
2. Leonard Davis Institute of Health Economics University of Pennsylvania Perelman School of Medicine Philadelphia PA
3. Gastroenterology Section Corporal Michael J. Crescenz VA Medical Center Philadelphia PA
4. Baylor University Medical Center Baylor Scott and White Health Dallas TX
5. Center for Clinical Effectiveness Baylor Scott and White Research Institute Dallas TX
6. Division of Digestive Diseases Yale University School of Medicine New Haven CT
7. VA Connecticut Healthcare System West Haven CT
8. Division of Gastroenterology and Hepatology Mayo Clinic College of Medicine and Science Rochester MN