1. Division of Gastroenterology and Hepatology; Department of Internal Medicine III; Medical University of Vienna; Vienna Austria
2. Department of Internal Medicine IV; Wilhelminenspital; Vienna Austria
3. Section for Medical Statistics; CeMSIIS; Medical University of Vienna; Vienna Austria
4. Inserm U954 and Department of Gastroenterology; Nancy University Hospital; Lorraine University; Vandoeuvre-les-Nancy France
5. Gastroenterology Department; IDIBAPS; CIBEREHD; Hospital Clinic Barcelona; Barcelona Spain
6. Division of Gastroenterology; Department of Internal Medicine; McMaster University; Hamilton ON Canada