1. Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden
2. Department of Surgery, Skellefteå County Hospital, Skellefteå, Sweden
3. Department of Surgical Sciences, Uppsala University, Uppsala, Sweden
4. Department of Surgery, Lund University, Lund, Sweden
5. Department of Digestive Surgery, Karolinska University Hospital, Stockholm, Sweden