1. Department of Physical Therapy, Faculty of Medicine, School of Health Sciences, University of Iceland, Reykjavik, Iceland
2. Landspitali - the National University Hospital of Iceland, Reykjavik, Iceland
3. Department of Physiotherapy, Landspitali - the National University of Hospital of Iceland, Reykjavik, Iceland
4. Department of Education and Science, Akureyri Hospital, Akureyri, Iceland