1. Digestive Endoscopy Unit, Catholic University, Rome, Italy
2. Department of Gastroenterology, Hepatopancreatology and Digestive Oncology, Erasme University Hospital, Brussels, Belgium
3. Department of Gastroenterology and Interventional Endoscopy, Klinikum Friedrichshain, Berlin, Germany
4. Department of Internal Medicine, Evangelisches Krankenhaus, Düsseldorf, Germany
5. Department of Gastroenterology, Maggiore Hospital, Crema, Italy
6. Department of Internal Medicine, St. Elisabeth Hospital,Vienna, Austria
7. Endoscopy Unit, Paoli-Calmettes Institute, Marseille, France
8. Department of Gastroenterology, Nuovo Regina Margherita Hospital, Rome, Italy
9. Gedyt Endoscopy Center, Buenos Aires, Argentina