A self-administered screener for migraine in primary care: The ID Migraine validation study.

BACKGROUND Migraine is a highly prevalent and disabling illness that remains substantially undiagnosed in primary care. Because of the potential value of a screening tool, the current study was designed to establish the validity and reliability of a brief, self-administered migraine screener in patients with headache complaints in the primary care setting. METHODS A total of 563 patients presenting for routine primary care appointments and reporting headaches in the past 3 months completed a self-administered migraine screener. All patients were then referred for an independent diagnostic evaluation by a headache expert, of whom 451 (80%) completed a full evaluation. Migraine diagnosis was assigned based on International Headache Society criteria after completing a semi-structured diagnostic interview. RESULTS Of nine diagnostic screening questions, a three-item subset of disability, nausea, and sensitivity to light provided optimum performance, with a sensitivity of 0.81 (95% CI, 0.77 to 0.85), a specificity of 0.75 (95% CI, 0.64 to 0.84), and positive predictive value of 0.93 (95% CI, 89.9 to 95.8). Test-retest reliability was good, with a kappa of 0.68 (95% CI, 0.54 to 0.82). The sensitivity and specificity of the three-item migraine screener was similar regardless of sex, age, presence of other comorbid headaches, or previous diagnostic status. CONCLUSIONS The three-item ID Migraine migraine screener was found to be a valid and reliable screening instrument for migraine headaches. Its ease of use and operating characteristics suggest that it could significantly improve migraine recognition in primary care.