[1] Fdn IRCCS Ist Neurol C Besta, Unit Neuroepidemiol, Milan, Italy
[2] Univ Turin, Dept Psychol, Turin, Italy
[3] Univ Lubeck, Inst Social Med & Epidemiol, Lubeck, Germany
[4] Univ Hosp Policlin Vittorio Emanuele, Multiple Sclerosis Ctr, Neurol Clin, Catania, Italy
[5] Univ Hosp Belgrade, CSS, Fac Med, Clin Neurol, Belgrade, Serbia
[6] Univ Hosp Vall dHebron, MS Ctr Catalonia Cemcat, Barcelona, Spain
[7] Marianne Strauss Klin, Kempfenhausen Ctr Treatment Multiple Sclerosis, Berg, Germany
[8] Univ Med Ctr Hamburg Eppendorf, Inst Neuroimmunol & Multiple Sclerosis, Hamburg, Germany
[9] Kings Coll Hosp NHS Fdn Trust, Dept Neurol, London, England
[10] Barzilai Govt Hosp, Ashqelon, Israel
[11] Ben Gurion Univ Negev, Beer Sheva, Israel
[12] Israel Multiple Sclerosis Soc, Tel Aviv, Israel
[13] Nieuw Unicum, Zandvoort, Netherlands
[14] Med Univ Sofia, Neurol Clin, Sofia, Bulgaria
[15] Univ Belgrade, Inst Epidemiol, Fac Med, Belgrade, Serbia
[16] Fdn IRCCS Casa Sollievo Sofferenza, Unit Biostat, San Giovanni Rotondo, Italy
[17] European Acad Neurol, Neurol Unit, Fdn IRCCS Casa Sollievo Sofferenza, San Giovanni Rotondo, Italy
[18] Multiple Sclerosis Int Federat, People MS Advisory Comm, Copenhagen, Denmark
[19] Univ Siena, Dept Life Sci, Siena, Italy
[20] Univ Hosp Cologne, Dept Palliat Med, Cologne, Germany
[21] FARO Charitable Fdn, Turin, Italy
[22] Univ Kent, Tizard Ctr, Canterbury, Kent, England