1. National Multiple Sclerosis Foundation, Rotterdam, The Netherlands;
2. Department of Psychology, Health, Medical and Neuropsychology Unit, Leiden University, Leiden, The Netherlands;
3. Department of Neurology, Elisabeth-TweeSteden Hospital, Tilburg, The Netherlands;
4. Department of Care Ethics, University of Humanistic Studies, Utrecht, The Netherlands;
5. Discipline of Psychology, School of Medicine, University of Tasmania, Tasmania, Australia;
6. MS4 Research Institute, Nijmegen, The Netherlands;
7. Department of Community and Occupational Medicine, University Medical Centre Groningen, Groningen, The Netherlands;
8. Department of Social and Behavioral Sciences, Tilburg University, Tilburg, The Netherlands;
9. Department of Rehabilitation, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands;
10. Department of Neurology, Medical Centre Leeuwarden, Leeuwarden, The Netherlands;
11. Department of Neurology, St. Antonius Hospital, Nieuwegein, The Netherlands;
12. Department of Neurology, Groene Hart Hospital, Gouda, The Netherlands;
13. Department of Neurology, Catharina Hospital, Eindhoven, The Netherlands;
14. Department of Neurology, Alrijne Hospital Leiden, Leiden, The Netherlands;
15. Department of Neurology, Rijnstate Hospital, Arnhem, The Netherlands;
16. Department of Neurology, Canisius-Wilhelmina Hospital, Nijmegen, The Netherlands;
17. Department of Neurology, Albert Schweitzer Hospital, Dordrecht, The Netherlands;
18. Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands