Early Management of OnabotulinumtoxinA Treatment in Chronic Migraine : Insights from a Real-Life European Multicenter Study - Ornello, Raffaele (University of L'Aquila. Neuroscience Section, Department of Applied Clinical Sciences and Biotechnology) ; Ahmed, Fayyaz (Hull University Teaching Hospitals) ; Negro, Andrea (Sapienza University) ; Miscio, Anna Maria (Fondazione IRCCS "Casa Sollievo Della Sofferenza") ; Santoro, Antonio (Fondazione IRCCS "Casa Sollievo Della Sofferenza") ; Alpuente, Alicia (Hospital Universitari Vall d'Hebron) ; Russo, Antonio (University of Campania "Luigi Vanvitelli") ; Silvestro, Marcello (University of Campania "Luigi Vanvitelli".) ; Cevoli, Sabina (IRCCS Istituto Delle Scienze Neurologiche Di Bologna) ; Brunelli, Nicoletta (Campus Bio-Medico University Hospital) ; Vernieri, Fabrizio (Campus Bio-Medico University Hospital) ; Grazzi, Licia (IRCCS Foundation "Carlo Besta" Neurological Institute) ; Baraldi, Carlo (University of Modena and Reggio Emilia) ; Guerzoni, Simona (University of Modena and Reggio Emilia) ; Andreou, Anna P. (Guy's and St Thomas' NHS Foundation Trust) ; Lambru, Giorgio (Guy's and St Thomas' NHS Foundation Trust) ; Frattale, Ilaria (Tor Vergata University) ; Kamm, Katharina (Ludwig Maximilians University München) ; Ruscheweyh, Ruth (Ludwig Maximilians University München) ; Russo, Marco (Azienda USL-IRCCS Di Reggio Emilia) ; Torelli, Paola (University of Parma) ; Filatova, Elena (Sechenov First Moscow State Medical University) ; Latysheva, Nina (Sechenov First Moscow State Medical University) ; Gryglas-Dworak, Anna (Headache Center Wroclaw) ; Straburzynski, Marcin (Terapia Neurologiczna Samodzielni) ; Butera, Calogera (IRCCS San Raffaele Scientific Institute (Milà, Itàlia)) ; Colombo, Bruno (IRCCS San Raffaele Scientific Institute (Milà, Itàlia)) ; Filippi, Massimo (IRCCS San Raffaele Scientific Institute (Milà, Itàlia)) ; Pozo-Rosich, Patricia (Hospital Universitari Vall d'Hebron) ; Martelletti, Paolo (Sapienza University'Andrea) ; Sacco, Simona (University of L'Aquila) ; Universitat Autònoma de Barcelona