[1] Univ Autonoma Barcelona, Headache & Craniofacial Pain Unit, Vall dHebron Res Inst VHIR,Dept Med, Hosp Univ Vall dHebron,Neurol Dept,Headache & Neu, Barcelona, Spain
[2] Bambino Gesu Pediat Hosp, Headache Ctr, Child Neurol Unit, Rome, Italy
[3] Univ Hosp Padua, Juvenile Headache Ctr, Dept Womans & Childs Hlth, Padua, Italy
[4] Univ Rome Sapienza, St Andrea Hosp, Dept Internal Med, Rome, Italy
[5] Erasmus MC, Dept Internal Med, Div Vasc Med & Pharmacol, Rotterdam, Netherlands
[6] Univ Palermo, Policlin Paolo Giaccone Hosp, Dept Biomed Neurosci & Adv Diagnost, Palermo, Italy
[7] Hosp Univ Clin San Carlos, Neurol Dept, Headache & Craniofacial Pain Unit, Madrid, Spain
[8] Univ Autonoma Madrid UAM, Hosp Univ La Princesa, Neurol Dept, Madrid, Spain
[9] Univ Autonoma Madrid UAM, Inst Invest Sanit La Princesa, Madrid, Spain
[10] Nikiforov Russian Ctr Emergency & Radiat Med EMER, Dept Clin Neurol & Sleep Med, St Petersburg, Russia
[11] Grevena Gen Hosp, Grevena, Greece
[12] Univ Bern, Univ Hosp Psychiat & Psychotherapy, Switzerland Univ Hosp Psychiat, Bern, Switzerland
[13] Med Ctr New Med Technol, Dept Neurol, Headache Unit, Voronezh, Russia
[14] Univ Hosp Donostia, Dept Neurol, San Sebastian, Spain
[15] Clin Univ Navarra, Dept Neurol, Pamplona, Spain
[16] Hosp Quironsalud Donostia, Dept Neurol, San Sebastian, Spain
[17] Univ Hosp Leuven, Dept Neurol, Leuven, Belgium
[18] State Inst Dnipropetrovsk Med Akad MOH Ukraine, Dept Neurol & Neurosurg, Dnipro, Ukraine
[19] Ghent Univ Hosp, Dept Neurol, Ghent, Belgium
[20] Erasmus MC, Dept Neurosci, Rotterdam, Netherlands
[21] Ordensklinikum Linz Barmherzige Schwestern, Headache Med Ctr Linz, Linz, Austria