1. Department of Acute and Digestive Surgery, Haukeland University Hospital, Bergen, Norway
2. Department of Clinical Medicine, University of Bergen, Bergen, Norway
3. Department of Oncology, Haukeland University Hospital, Bergen, Norway
4. Department of Clinical Science, University of Bergen, Bergen, Norway
5. Centre for Clinical Research, Department of Research and Development, Haukeland University Hospital, Bergen, Norway
6. Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway