1. CTO Hospital, Digestive Endoscopy Unit, Iglesias, Italy
2. Russell Hall, Dept. of Gastroenterology, Birmingham, United Kingdom
3. Birmingham City University, Birmingham, United Kingdom
4. Nuovo Regina Margherita Hospital, Gastroenterology, Italy
5. Portsmouth University Hospital, Dept. of Gastroenterology, Portsmouth, United Kingdom
6. University Medical Center Mainz, Interventional Endoscopy Center, I. Medizinische Klinik und Poliklinik, Mainz, Germany
7. National Hospital Organization Kure Medical Center and Chugoku Cancer Center, Gastroenterology, Kure, Japan
8. Osaka International Cancer Institute, Department of Gastrointestinal Oncology, Osaka, Japan
9. NIHR Nottingham Digestive Diseases Biomedical Research Centre, Nottingham University Hospitals NHS Trust, Gastroenterology, Nottingham, United Kingdom
10. VU University Medical Center, Dept. of Gastroenterology, Arnhem, Netherlands
11. California Pacific Medical Center, California, United States
12. Veteran Affairs Greater Los Angeles Healthcare System, Sepulveda Ambulatory Care Center, California, United States
13. David Geffen School of Medicine at UCLA, Medicine, North Hills, California, United States.