Towards a functional model of chronic headaches: investigation of antecedents and consequences.

The traditional approach to classifying headache based on symptoms and assumed mechanisms is criticized as having limited utility when applied to tension-type headache and migraine. The study reported here was designed to explore an alternative method of conceptualizing chronic headaches based on functional characteristics or controlling variables. One hundred and ninety nine chronic headache sufferers completed questionnaires which enquired about the antecedents and consequences of their headaches. An attempt to build a categorical model driven by functional characteristics using cluster analysis was unsuccessful but a subsequent attempt to construct a dimensional model using factor analysis proved more successful. This approach led to the emergence of five antecedent dimensions and six consequences dimensions (three pertaining to the responses of sufferers and three to the reactions of significant others) which were readily identifiable. The functional dimensions were significantly related to traditional diagnostic categories but at a low level. Three functional dimensions predicted response to psychological treatment.