Overview of the international classification of headache disorders (ICHD III)

Abstract

In order to effectively study and manage headache disorders, diagnosis is essential. In both research and clinical areas, separating second ary causes from primary headache disorders is acrucial first step, followed by further specificity within these broader categories. Historical approaches to classifying headache disorders culminated in the International Classification of Headache Disorders (ICHD), published in 1988. This was revised as the International Classification of Headache Disorders, (ICHD II) in 2004. The International Headache Society’s Subcommittee on Classification began work on the 3rd edition in 2010. ICHD-3 was published as the first issue of Cephalalgia in 2018, followed the publication of ICHD-3 beta version in 2013. The idea behind the beta version was to promote more field testing before presentation of the final ICHD-3. There have been excel lent field-testing studies published, in migraine with aura, cluster headache, idiopathic intracranial hypertension and trigeminal neuralgia among others. Consequently, these sym toms are included only in the Appendix of ICHD-3, where they in vite further study. These are examples of the evidence based process of disease classification that now underpins all future changes to the ICHD. The diagnostic criteria for more than 200 causes of headaches are based upon evidence when available, of a number of primary and secondary headache disorders.