1. Department of Medicine and Gastroenterology, Protestant Deaconess Hospital (Evangelisches Diakoniekrankenhaus) Freiburg, Academic Teaching Hospital, University of Freiburg
2. Department of Gastroenterology, Asklepios Clinic Altona, Academic Teaching Hospital University of Hamburg, Hamburg
3. Department of Gastroenterology, Hepatology, and Endoscopy, Asklepios Clinic Barmbek, Academic Teaching Hospital University of Hamburg, Hamburg
4. Department of Gastroenterology, Sana Hospital Lichtenberg, Academic Teaching Hospital, University of Berlin, Berlin, Germany
5. Department of Medicine II, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg