1. Department of Gastroenterology, Hospital Universitario Rio Hortega, Valladolid, Spain
2. Universitat Autònoma de Barcelona, Barcelona, Spain
3. Hospital General Universitario de Alicante, Alicante, Spain
4. Hospital Clínico Universitario de Valencia, Valencia, Spain
5. Endoscopy Unit, Department of Digestive Diseases, Hospital Universitari de Bellvitge, Bellvitge Biomedical Research Institute (IDIBELL), University of Barcelona, Barcelona, Spain
6. Department of Gastroenterology, Hospital Universitari Mútua Terrassa, Fundació per la Recerca Mútua Terrassa, Barcelona, Spain
7. Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Spain
8. Hospital Universitario Virgen del Rocío, Seville, Spain
9. Hospital Universitario Marqués de Valdecilla, Santander, Spain
10. Endoscopy Unit, Department of Gastroenterology and Hepatology, Hospital Ramón y Cajal, IRYCIS, Madrid, Spain
11. Hospital General Universitario de Castellón, Castellón, Spain
12. Hospital General Universitario Gregorio Marañon, Madrid, Spain
13. Department of Gastroenterology, Endoscopy Unit, University of Navarra Clinic, University of Navarra, Pamplona, Spain
14. Hospital General Río Carrión, Palencia, Spain
15. Hospital General Universitario de Elche, Alicante, Spain
16. Complejo Hospitalario de Navarra, Pamplona, Spain
17. Hospital Regional de Málaga, Málaga, Spain
18. Hospital Universitari Germans Trias i Pujol, Badalona, Spain
19. Hospital Universitari de Girona Josep Trueta, Girona, Spain
20. Department of Gastroenterology, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Spain