Burden and attitude to resistant and refractory migraine: a survey from the European headache federation with the endorsement of the European migraine & headache alliance

Simona Sacco^*, Christian Lampl, Antoinette Maassen van den Brink, Valeria Caponnetto, Mark Braschinsky, Anne Ducros, Patrick Little, Patricia Pozo-Rosich, Uwe Reuter, Elena Ruiz de la Torre, Margarita Sanchez Del Rio, Alexandra J. Sinclair, Paolo Martelletti, Zaza Katsarava, Burden and Attitude to Resistant and Refractory (BARR) Study Group, Raquel Gil-Gouveia