1. U. Petursdottir, PT, MS, is Physical Therapist, Bjarg Rehabilitation Center, Bugdusida 1, 603 Akureyri, Iceland. Mrs Petursdottir was a student at the University of Akureyri, Akureyri, Iceland, at the time this research was completed in partial fulfillment of the requirements for her Master of Science degree in health sciences.
2. S.A. Arnadottir, PT, MS, is Assistant Professor, School of Health Sciences, University of Akureyri.
3. S. Halldorsdottir, PhD (Med Dr), is Professor and Chairman of the Faculty of Graduate Studies, School of Health Sciences, University of Akureyri.