1. Department of Gastroenterology and Hepatology, Medical Centre for Postgraduate Education, Maria Sklodowska-Curie Memorial Cancer Centre and Institute of Oncology, Warsaw, Poland
2. Digestive Endoscopy Unit, Nuovo Regina Margherita Hospital, Rome, Italy
3. Department of Gastroenterology, University Hospital Leuven, Leuven, Belgium
4. Department of Gastroenterology and Interventional Endoscopy, Klinikum im Friedrichshain, Berlin, Germany
5. Department of Gastroenterology, Institut de Malaties Digestives i Metabòliques, Hospital Clinic, Barcelona, Spain
6. Department of Gastroenterology and Hepatology, Academic Medical Centre, Amsterdam, The Netherlands
7. Wolfson Unit for Endoscopy, St Mark's Hospital, Imperial College London, UK
8. Medizinische Klinik, St. Mary Hospital, Frankfurt, Germany
9. Department of Gastroenterology, Queen Alexandra Hospital, Portsmouth Hospitals NHS Trust, Portsmouth, United Kingdom
10. Department of Gastroenterology, University Hospital, CHU Rennes, France
11. Gedyt Endoscopy Center, Buenos Aires, Argentina
12. Translational Gastroenterology Unit, John Radcliffe Hospital, Oxford University, Oxford, United Kingdom.