The international classification of headache disorders. 2nd edition (ICHD-II).

The universally accepted international classification of headache disorders, first published in 1988, has now been replaced by a second edition ICDH-2. It is important to implement the new edition immediately since there are many important changes compared with the first edition. Application of the new edition is the only way to assure that the same diagnostic approach and appropriate treatment are provided for all headache patients.