1. National Advisory Unit on Rehabilitation in Rheumatology, Diakonhjemmet Hospital; Oslo Norway
2. Institute of Health and Society, University of Oslo, and National Advisory Unit on Rehabilitation in Rheumatology, Diakonhjemmet Hospital; Oslo Norway
3. Oslo University Hospital; Oslo Norway
4. Institute of Health and Society; University of Oslo Norway
5. Diakonhjemmet Hospital; Oslo Norway