1. Headache and Pain Unit, IRCCS San Raffaele, Via della Pisana 235, 00163 Rome, Italy
2. San Raffaele University, 00166 Rome, Italy
3. Headache Center Neurology Unit, San Giuseppe Moscati Hospital, 83100 Avellino, Italy
4. Laboratory of Neurosciences, Department of Neurology-Stroke Unit, Istituto Auxologico Italiano, IRCCS, 20145 Milan, Italy
5. Department of Clinical and Experimental Medicine, University of Messina, 98122 Messina, Italy
6. Neurology Unit, IRCCS San Raffaele Scientific Institute, Vita-Salute San Raffaele University, 20132 Milan, Italy
7. Clinical and Molecular Epidemiology, IRCCS San Raffaele, 00166 Rome, Italy