1. Headache and Pain Unit, IRCCS San Raffaele Rome; San Raffaele University, Rome
2. Headache and Pain Unit, IRCCS San Raffaele Rome
3. Neurology Unit, Department of Medicine and Surgery, Headache Center, University of Parma
4. Neurology Unit, San Paolo Hospital, ASL 2 Savona
5. Neurology Unit, San Giuseppe Moscati Hospital Avellino
6. Campus Bio-Medico University Hospital, Rome
7. Department of Vision and Neurological Sciences, Spedali Civili, Brescia
8. Department of Neurology-Stroke Unit, Laboratory of Neuroscience, Istituto Auxologico Italiano, IRCCS, Milan
9. Headache Center, Neurology Unit, San Camillo-Forlanini Hospital, Rome
10. Neurology Unit and Stroke-Unit, AORN A. Cardarelli, Naples
11. Department of Clinical and Experimental Medicine, University of Messina
12. Department of Neuroscience, Mental Health and Sensory Organs (NESMOS), “Sapienza” University of Rome, Sant'Andrea University Hospital, Rome
13. Headache Unit, Department of Neurology, Scientific Institute San Raffaele Hospital, Vita-Salute University, Milan
14. Headache Center, Neurology Unit, San Filippo Neri Hospital, Rome
15. Neurology and Stroke Unit, Cardinal Massaia Hospital, Asti
16. Stroke Unit, S. Camillo de Lellis Hospital, Rieti
17. Pediatric Headache Center, Neurology Unit, University of Sassari
18. Headache Center, ASST Santi Paolo Carlo, Milan
19. IRCCS San Raffaele Rome
20. Clinical and Molecular Epidemiology, IRCCS San Raffaele Rome
21. Clinical and Molecular Epidemiology, IRCCS San Raffaele Roma, Italy; Department of Human Sciences and Quality of Life Promotion, San Raffaele University, Rome, Italy.