Correction to: A PRISMA-compliant systematic review of the endpoints employed to evaluate symptomatic treatments for

D García-Azorin1, N Yamani2,3, L M Messina4,5

  • 1Headache Unit Neurology Department, Hospital Clínico Universitario Valladolid, Avda. Ramón y Cajal 3, 47005, Valladolid, Spain. davilink@hotmail.com.

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