Headache syndromes as detected by configural frequency analysis

Data on headache symptoms obtained in two samples (N = 422 and 304) by means of questionnaires were subjected to configural frequency analysis (CFA). This not widely-known method tests whether certain symptom combinations appear more often or less often than expected by chance. In both samples symptom combinations corresponding to the syndromes of migraine with aura, migraine without aura and tension headache did indeed occur with significant frequency. The same clear-cut symptom patterns appeared when patients with preceding visual disturbances were excluded from analysis. These results seem to lend strong support to a categorical model of headache, rather than to the concept of headache as a spectrum.