Development of diagnostic criteria for headache syndromes: lessons from psychiatry.

This paper reviews the development of diagnostic criteria for the psychiatric disorders in order to provide a model for the development of classification of headache. The strengths and weaknesses of the current psychiatric classification system, and procedures that have been instituted to strengthen the next version of the classification are described. The problems that characterized the successive versions of the criteria are highlighted in order to stimulate future developments of diagnostic criteria for headache syndromes. Recommendations for application of these principles to headache classification are presented.