1. Division of Gastroenterology; Duke University School of Medicine; Durham North Carolina USA
2. Division of Gastroenterology; Icahn School of Medicine at Mt. Sinai; New York New York USA
3. Center for Evidence-based Practice; University of Pennsylvania; Philadelphia Pennsylvania USA
4. Division of Gastroenterology; University of Pennsylvania; Philadelphia Pennsylvania USA
5. Department of Biostatistics and Epidemiology; University of Pennsylvania; Philadelphia Pennsylvania USA
6. Leonard Davis Institute of Health Economics; University of Pennsylvania; Philadelphia Pennsylvania USA
7. Center for Clinical Epidemiology and Biostatistics; University of Pennsylvania; Philadelphia Pennsylvania USA
8. Division of General Internal Medicine, Perelman School of Medicine; University of Pennsylvania; Philadelphia Pennsylvania USA