1. Unit of Neuroepidemiology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
2. School of Psychology, Faculty of Health and Behavioural Sciences, University of Queensland, St Lucia, Australia
3. Unit of Neuroimmunology and Neuromuscular Diseases, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
4. Italian Multiple Sclerosis Society and Research Foundation (FISM), Genoa, Italy