Headache: what to ask, how to examine, and what scales to use. Recommendations of the Spanish society of neurology¿s headache study group A.B. Gago-Veiga; J. Camiña Muñiz; D. García-Azorín; V. González-Quintanilla; C.M. Ordás; M. Torres-Ferrus; S. Santos-Lasaosa; J. Viguera-Romero; P. Pozo-Rosich;