1 Department of Surgery, Institute of Clinical Sciences, Gothenburg University SSORG-Scandinavian Surgical Outcomes Research Group Sahlgrenska University Hospital/Östra Gothenburg, Sweden Department of Surgery, Institute of Clinical Sciences, Gothenburg University SSORG-Scandinavian Surgical Outcomes Research Group Sahlgrenska University Hospital/Östra Gothenburg, Sweden SSORG-Scandinavian Surgical Outcomes Research Group Department of Surgery Herlev University Hospital Copenhagen, Denmark Department of Surgery, Institute of Clinical Sciences, Gothenburg University SSORG-Scandinavian Surgical Outcomes Research Group Sahlgrenska University Hospital/Östra Gothenburg, Sweden.