1. Division of Gastroenterology and Hepatology, Medical University of South Carolina, Charleston, South Carolina, USA;
2. Division of Gastroenterology and Hepatology, Penn State Hershey Medical Center, Hershey, Pennsylvania, USA;
3. Division of Gastroenterology, Mayo Clinic Florida, Jacksonville, Florida, USA;
4. Division of Digestive and Liver Diseases, University of Texas Southwestern, Dallas, Texas, USA;
5. Department of Population and Data Sciences, University of Texas Southwestern, Dallas, Texas, USA;
6. Division of Gastroenterology and Hepatology, University of Virginia, Charlottesville, Virginia, USA;
7. Vatche & Tamar Manoukian Division of Digestive Diseases, UCLA School of Medicine, Los Angeles, California, USA;
8. MUSC Libraries, Medical University of South Carolina, Charleston, South Carolina, USA;
9. Health Sciences Library, University of Virginia, Charlottesville, Virginia, USA;
10. Mayo Clinic Libraries, Mayo Clinic Florida, Jacksonville, Florida, USA.