1. Department of Public Health, University Medical Center Rotterdam, Rotterdam, The Netherlands
2. Department of Neurology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
3. Department of Clinical Neuropsychology, University of Groningen, Groningen, The Netherlands
4. Department of Physical Medicine and Rehabilitation, Spaulding Rehabilitation Hospital, Spaulding Research Institute, Harvard Medical School; Home Base, A Red Sox Foundation and Massachusetts General Hospital Program, Boston, Massachusetts, USA