[1] Univ Med Ctr Hamburg Eppendorf, Inst Neuroimmunol & Multiple Sclerosis, Hamburg, Germany
[2] Carl von Ossietzky Univ Oldenburg, Dept Hlth Serv Res, Oldenburg, Germany
[3] Univ Cologne, Univ Hosp Cologne, Inst Nursing Sci, Cologne, Germany
[4] Univ Cologne, Fac Med, Cologne, Germany
[5] Heinrich Heine Univ Dusseldorf, Ctr Hlth & Soc, Inst Hlth Serv Res & Hlth Econ, Dusseldorf, Germany
[6] MS Forsch & Projektentwicklungs gGmbH, Hannover, Germany
[7] Stiftung Selbstbestimmung & Selbstvertretung MS B, Trier, Germany
[8] Univ Med, Dept Med Stat, Gottingen, Germany
[9] Univ Med Ctr Hamburg Eppendorf, Dept Neurol, Hamburg, Germany