1. Department of Surgery, Department of Clinical Sciences, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
2. Department of Surgery (Östra Sjukhuset), Sahlgrenska University Hospital, Gothenburg, Sweden
3. Department of Clinical Sciences, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden
4. Department of Surgery, Ersta Hospital, Stockholm, Sweden
5. Department of Surgery, Mora Hospital, Mora, Sweden
6. Department of Clinical Sciences, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden
7. Finnish Institute for Health and Welfare, Helsinki, Finland
8. Department of Surgery, Vrinnevi Hospital, Norrköping, Sweden
9. Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
10. Department of Endocrinology, Obesity, and Nutrition, Vestfold Hospital Trust, Tønsberg, Norway
11. Department of Surgery, Vestfold Hospital Trust, Tønsberg, Norway
12. Department of Surgery, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
13. Division of Clinical Epidemiology, Department of Medicine (Solna), Karolinska Institutet, Stockholm, Sweden
14. Wallenberg Centre for Molecular Medicine, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
15. for the BEST Study Group