1. Department of Surgery, University Hospital Maastricht, Maastricht, The Netherlands
2. Karolinska Institute, Clintec, Division of Surgery, Karolinska University Hospital, Huddinge and Centre of Gastrointestinal Disease, Ersta Hospital, Stockholm, Sweden
3. Department of Gastrointestinal Surgery, University Hospital Northern Norway, Tromsø, Norway
4. Department of Surgical Gastroenterology, Hvidovre University Hospital, Hvidovre, Denmark
5. Department of Clinical Epidemiology and Medical Technology Assessment, University Hospital Maastricht, Maastricht, The Netherlands
6. Section of Surgical Pathophysiology, Rigshospitalet, Copenhagen, Denmark
7. Clinical and Surgical Sciences (Surgery), Royal Infirmary, Edinburgh, UK