1. Division of Sport Sciences, Department of Health Sciences, Lund University, Lund, Sweden
2. Clinical Epidemiology Unit, Department of Clinical Sciences Lund, Orthopedics, Lund University, Lund, Sweden
3. Arthro Therapeutics, Malmö, Sweden
4. Centre for Clinical Research, Uppsala University, Västerås, Sweden
5. Department of Community Medicine and Rehabilitation, Umeå University, Umeå, Sweden