[1] Univ Aquila, Neurosci Sect, Dept Appl Clin Sci & Biotechnol, Laquila, Italy
[2] Univ Modena & Reggio Emilia, Sch Neurosci, Dept Biomed Metab & Neural Sci, Modena, Italy
[3] Univ Modena & Reggio Emilia, Dept Biomed Metab & Neural Sci, Med Toxicol Headache & Drug Abuse Res Ctr, Modena, Italy
[4] Guys & St Thomas Natl Hlth Serv NHS Fdn Trust, Headache Serv, London, England
[5] Charite Univ Med Berlin, Dept Neurol, Berlin, Germany
[6] Praxis Gendolla, Essen, Germany
[7] Ist Ricovero & Cura Carattere Sci IRCCS San, Headache & Pain Unit, Rome, Italy
[8] San Raffaele Univ, Rome, Italy
[9] Ist Ricovero & Cura Carattere Sci IRCCS, Ist Sci Neurol Bologna, Bologna, Italy
[10] Policlin Univ Campus Bio Med, Headache & Neurosonol Unit, Rome, Italy
[11] Univ Campania Luigi Vanvitelli, Dept Med Surg Neurol Metab & Aging Sci, Headache Ctr, Naples, Italy
[12] Osped S Antonio Abate, Headache Ctr, ASST Valle Olona, Gallarate, Italy
[13] Cardarelli Hosp, Div Neurol & Stroke Unit, Headache Ctr, Naples, Italy
[14] Sechenov First Moscow State Med Univ, Sechenov Univ, Moscow, Russia
[15] Derriford Hosp, Dept Neurol, Southwest Neurol Audit & Res Grp, Plymouth, Devon, England
[16] Alfred Hlth, Dept Neurol, Melbourne, Vic, Australia
[17] Univ Hosp Essen, Dept Neurol, West German Headache Ctr, Essen, Germany
[18] Charles Univ Prague, Mil Univ Hosp Prague, Dept Neurol, Fac Med 1, Prague, Czech Republic
[19] Charles Univ Prague, Motol Univ Hosp Prague, Dept Neurol, Fac Med 1, Prague, Czech Republic
[20] G Mazzini Hosp, Dept Neurol, Teramo, Italy
[21] F Renzetti Hosp, Dept Neurol, Chieti, Italy
[22] S Pio Pietrelcina Hosp, Dept Neurol, Chieti, Italy
[23] Univ G dAnnunzio, Dept Med & Sci Aging, Headache Ctr, Geriatr Clin, Chieti, Italy
[24] Univ G dAnnunzio, Ctr Adv Studies & Technol, Headache Ctr, Geriatr Clin, Chieti, Italy
[25] Univ Med Greifswald, Greifswald, Germany