1. Department of Rehabilitation Medicine, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands;
2. Institute for Sports Studies, Hanze University of Applied Sciences, Groningen, The Netherlands;
3. Department of Physical Therapy, University of Alberta, Edmonton, Canada;
4. Rehabilitation Centre Valens, Valens, Switzerland;
5. Center for Disability Research, Liberty Mutual Research Institute for Safety, Boston, MA, USA;
6. Massachusetts General Hospital, Institute for Health Professions, Boston, MA, USA;
7. Department of Work Rehabilitation, Rehaklinik Bellikon, Bellikon, Switzerland