1. Department of Digestive Diseases, Complexo Hospitalario Universitario de Ourense, Ourense, Spain
2. Endoscopy Unit, Department of Digestive Diseases, Hospital Universitari de Bellvitge, Bellvitge Biomedical Research Institute (IDIBELL), University of Barcelona, Barcelona, Spain
3. Department of Surgery, Hospital Universitari de Bellvitge, Bellvitge Biomedical Research Institute (IDIBELL), University of Barcelona, Barcelona, Spain
4. Statistics Advisory Service, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain
5. Hepatology Unit, Department of Digestive Diseases, Hospital Universitari de Bellvitge, Bellvitge Biomedical Research Institute (IDIBELL), University of Barcelona, Barcelona, Spain