title: Classification of headache disorders.
abstract: Clinical diagnostic classifications are critical when clear biological markers are not available. Such is the case in many headache disorders and mental disorders. Also, it is crucial that the classification is widely accepted and utilized. A main goal of classification is to be a universal language for categorizing a disease or a set of disorders, establishing diagnostic criteria, and promoting unity in treatment. The International Headache Society published its first Classification of Headache Disorders in 1988 and its second edition in 2004. The first classification paved the way for a better understanding of the epidemiology, mechanisms, and treatment of headache disorders, and the second edition likely will magnify our knowledge. This article provides an overview of the classification system and outlines some of the major changes in the revised edition.
authors.affiliation: Department of Neurology, The Chicago Medical School at Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064, USA.
authors.forename: Nabih M
authors.initials: NM
authors.lastname: Ramadan
authors.forename: Jes
authors.initials: J
authors.lastname: Olesen
mesh_terms: D003937:Diagnosis, Differential; D020773:Headache Disorders / Q000145:classification* / Q000175:diagnosis / Q000266:history; D049673:History, 20th Century; D049674:History, 21st Century; D006801:Humans; D038801:International Classification of Diseases