Background.—The authors recently developed a software program designed to analyze clinical data from patients affected by primary headache. The program is based exclusively on the International Classification of Headache Disorders 2nd edition (ICHD-II) criteria. This software examines all the diagnoses of primary headaches on the basis of the variables needed to fulfill these mandatory criteria.
Methods.—We tested the software, Primary Headaches Analyser 1.0 INT (PHA), by entering and analyzing clinical data from 200 consecutive patients affected by primary chronic headaches and evaluating the corresponding output diagnoses.
Results.—The diagnosis of chronic migraine (1.5.1) was obtained in 68 cases (34 %) and that of probable chronic migraine (1.6.5) plus probable medication-overuse headache (8.2.8) in 46 (23%). Chronic tension-type headache (2.3) and probable chronic tension-type headache (2.4.3) plus probable medication-overuse headache (8.2.8) were diagnosed in 24 (12%) and 2 (1%) patients, respectively. Moreover, 4 and 12 patients, respectively, received both the diagnosis of chronic migraine (1.5.1) plus chronic tension-type headache (2.3) and of probable migraine (1.6.1) without aura plus chronic tension-type headache (2.3). In the remaining 44 cases (22%), none of the chronic primary headaches disorders defined by ICHD-II received an output diagnosis from the program. This was due mainly to the fact that the criteria fulfilled were insufficient for the diagnoses of migraine without (1.1) aura plus chronic migraine or, more infrequently, chronic tension-type headache.
Conclusions.—Our software program permitted diagnoses of chronic migraine, chronic tension-type or their probable forms (with or without MOH) in 78% of 200 patients with headache 15 or more days per month. In the remaining cases the inability to provide a specific diagnosis may be explained in part by the fact that the criteria for both diagnoses are too stringent and do not accurately reflect variations of the headache pattern in these chronic forms.