University of Amsterdam - Amsterdam University Medical Centers, University of Amsterdam - Amsterdam UMC, University of Amsterdam - Amsterdam Gastroenterology Endocrinology & Metabolism (AGEM), Unidade Local de Saúde de Entre Douro e Vouga (ULSEDV), University of Barcelona, Ruhr University of Bochum, Ghent University, University of Amsterdam - Department of Surgery, University of Pisa - Department of Translational Research on New Technologies in Medicine and Surgery, Maastricht University, Erasmus University Rotterdam (EUR) - Department of Gastroenterology & Hepatology, University of Amsterdam - Amsterdam UMC, Trinity College (Dublin), Beaujon Hospital, Università Vita-Salute San Raffaele - IRCCS Ospedale San Raffaele, Karolinska Institutet - Karolinska University Hospital, Ghent University, Erasmus University Rotterdam (EUR) - Erasmus Medical Center (MC), Liv Bona Dea Hospital, University of Hamburg - University Medical Center Hamburg-Eppendorf, University of Groningen, University of Helsinki, Beaujon Hospital, Leiden University, Humanitas University, Riga East University Hospital, Riga East University Hospital, University of Antwerp, University of Hamburg - University Medical Center Hamburg-Eppendorf, Università Vita-Salute San Raffaele - IRCCS Ospedale San Raffaele, University of Oslo - Oslo University Hospital, Ruhr University of Bochum, University of Hamburg - University Medical Center Hamburg-Eppendorf, University of Amsterdam - Amsterdam University Medical Centers, Erasmus University Rotterdam (EUR) - Department of Surgery, Leiden University, St. Antonius Hospital, St. Antonius Hospital, University of Amsterdam - Amsterdam University Medical Centers, University of Oslo - Oslo University Hospital, University of Amsterdam - Amsterdam University Medical Centers, Independent and Independent