1. Department of Neurology, University Medicine Greifswald, Ferdinand-Sauerbruchstraße, Greifswald 17475, Germany
2. German MS Register by the German MS Society, MS Research and Project Development gGmbH [MSFP], Hanover, Germany
3. Department of Neurology, Medical University of Vienna, Vienna, Austria
4. Department of Neurology, Neuroimmunological Section, University of Rostock, Rostock, Germany