Validation of a headache questionnaire in an outpatient clinic of an university hospital

Headache is a common complaint with a high prevalence in ambulatory settings. The physical and neurological examinations are frequently normal. The use of questionnaires as a screening method for patients with primary headache could facilitate the diagnosis in non specialized medical centers. In the present study, we used a questionnaire, based on the IHS criteria and modified by the authors, applied to 204 patients from the outpatient clinic of the Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo. Half of the patients were submitted to a clinical interview. We compared the results of the questionnaire with the results of the medical interview (gold standard). Most of the headaches we studied were primary headaches (89.6%). The questionnaire revealed a sensitivity of 90.2% and specificity of 57.9% for migraine detection with a chance corrected agreement (kappa) of 0.47 and a positive predictive (PPV) value of 65.7% and a negative predictive value (NPV) de 86.8%. The sensitivity for tension-type headache detection was 60.8% and the specificity 87.1% with a kappa value of 0.49 and a PPV of 77.8% and a NPV of 75.9%. We conclude that this questionnaire can be used as a screening method for diagnosing headache and that it can be applied by non-medical personnel. This questionnaire could also be used For population studies.