1. Department of General, Visceral-, Thoracic-, Transplantation- and Paediatric Surgery, University Medical Center Schleswig-Holstein (UKSH), Campus Kiel, Kiel, Germany
2. Department of General Surgery, University Hospital Rostock, Rostock, Germany
3. Department of General Surgery and Thoracic Surgery, Hospital of Lueneburg, Lueneburg, Germany
4. Medical Department I, University Hospital Dresden, TU Dresden, Dresden, Germany
5. Department of Internal Medicine, Gastroenterology, Sophien-u. Hufeland Hospital, Weimar, Germany
6. Department of Internal Medicine I, University Medical Centre Schleswig-Holstein (UKSH), Campus Kiel, Kiel, Germany
7. Aesculap AG, Medical Scientific Affairs, Tuttlingen, Germany
8. Department of Surgery, Israelitisches Krankenhaus, Hamburg, Germany