title: Medication overuse headache in Canada.
authors.affiliation: Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada.
authors.forename: W J
authors.initials: WJ
authors.lastname: Becker
authors.forename: R A
authors.initials: RA
authors.lastname: Purdy
mesh_terms: D001294:Attitude to Health; D002170:Canada / Q000453:epidemiology; D051271:Headache Disorders, Secondary / Q000453:epidemiology* / Q000628:therapy; D006801:Humans