1. School of Health Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
2. University Health Care Research Center, Faculty of Medicine and Health, Örebro University, Örebro, Sweden
3. Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
4. Centre for Research and Development, Region Gävleborg/Uppsala University, Gävle, Sweden
5. Centre for Augmentative and Alternative Communication, University of Pretoria, Pretoria, South Africa
6. CHILD, Swedish Institute for Disability Research, Jönköping University, Jönköping, Sweden
7. Center for Clinical Research Dalarna, Uppsala University, Uppsala, Sweden
8. Downstate Medical Center, State University of New York, Brooklyn, NY, United States