University of Genova - Section of Biostatistics, University of Genova - Department of Health Sciences, University of Genova - Section of Biostatistics, Centro Sclerosi Multipla ASST Spedali Civili di Brescia, Università Vita-Salute San Raffaele, ASST Papa Giovanni XXIII - Department of Neurology and Multiple Sclerosis Center, Ospedale Guglielmo da Saliceto - Multiple Sclerosis Center, San Luigi Gonzaga University Hospital, ASST-Spedali Civili of Brescia, Italian MS Foundation, Universita di Cagliari, IRCCS Istituto delle Scienze Neurologiche di Bologna (ISNB), City of Health and Science University Hospital of Turin - Department of Neuroscience - MS Center, Centro SM UOC Neurologia, Fidenza, AUSL PR, University of Pavia, Fondazione IRCCS Istituto Neurologico ‘Carlo Besta’, University of Rome Tor Vergata, University of Padua, IRCCS Ospedale Policlinico San Martino, Università degli Studi di Bari “Aldo Moro” (UNIBA), University of Naples Federico II, University of Campania Federico II, Università Vita-Salute San Raffaele, University of Siena - Department of Life Sciences, University of Catania, Sapienza University of Rome - Department of Neuroscience, Mental Health and Sensory Organs, Center for Experimental Neurological Therapies (CENTERS) and Independent