1. Department of Community Medicine and Rehabilitation, Umeå University, Umeå, Sweden
2. Unit of Research, Education and Development, Östersund Hospital, Östersund, Sweden
3. Research and Development Unit, Kommunförbundet Västernorrland, Härnösand, Sweden
4. Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden
5. Department of Public Health and Clinical Medicine, Medicine, Umeå University, Umeå, Sweden