1. Department of Surgical and Perioperative Sciences, Surgery, Umeå University, Umeå, Sweden
2. Wallenberg Centre for Molecular Medicine, Umeå University, Umeå, Sweden
3. Department of Statistics, Umeå School of Business, Economics and Statistics, Umeå University, Umeå, Sweden
4. Department of Molecular Medicine and Surgery, Karolinska Institutet, and Department of Surgery, Ersta Hospital, Stockholm, Sweden
5. Department of Surgery, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
6. Department of Surgery, Skåne University Hospital, Malmö, Lund University, Lund, Sweden
7. Department of Surgery, SSORG – Scandinavian Surgical Outcomes Research Group, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden