The diagnosis of migraine and tension-type headache, then and now.

Making an accurate headache diagnosis is important, and most medical personnel believe that they can do it properly. Until 1988, the diagnostic schema of the Ad Hoc Committee had been used, but it was found to be vague and too general. The operational criteria proposed by the Classification Committee of the International Headache Society (IHS) and published in Cephalalgia in 1988 are more specific. Their strong and weak points are reviewed and compared with the older criteria. The literature is reviewed with the conclusion that although the IHS criteria are not perfect, they represent a positive step. Further study will help to refine the criteria to make them more accurate and easier to use.