1. Department of Neurology, Hospital Universitario Quirónsalud, Madrid, Spain
2. Contractor to Sanofi Genzyme, Cambridge, MA, USA
3. Sanofi, Cambridge, MA, USA; Bristol-Myers Squibb, Lawrence Township, NJ, USA
4. Sanofi, Cambridge, MA, USA; Cerevance, Inc., Boston, MA, USA
5. Sanofi, Cambridge, MA, USA
6. Department of Medical Social Sciences, Center for Patient-Centered Outcomes, Institute for Public Health and Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA