1. Norwegian Arthroplasty Register, Department of Orthopaedic Surgery, Haukeland University Hospital, Bergen;
2. Department of Clinical Medicine (K1), Faculty of Medicine and Dentistry, University of Bergen, Bergen;
3. Department of Orthopaedic Surgery, Haugesund Hospital, Helse Fonna HF, Haugesund;
4. Department of Occupational Medicine, Haukeland University Hospital, Bergen, Norway;
5. AOA (Australian Orthopaedic Association) National Joint Replacement Registry, SAHMRI (South Australia Health and Research Institute), Adelaide, Australia