Author's response to reviews Title: Diagnosing migraine in research and clinical settings: The Validation of the Structured Migraine Interview (SMI) Authors:

R. The notion on specificity is overemphasized in the results as the result is based on evaluation of only 6 persons. A. The modest number has been addressed under results in this response and added under discussion pages 12-13 in the manuscript as described below: “Although the numbers are small, we believe that the results are able to demonstrate specificity and sensitivity, and are in keeping with larger sample sizes (Rasmussen et al 1991 Headache 31(5): 290-295). A previous study employing similar methodology also included a modest sample size of 61 headache sufferers concluded a combination of using a diary and a clinical interviewing was more effective than either method alone (Russell et al Cephalalgia 1992). In addition to the 41 individuals who their diagnoses were confirmed by the headache specialist in this study, 646 subjects who were attending the headache clinic and received formal diagnosis for their headaches were tested using the SMI. Although the reported diagnoses were by self report, the diagnosis obtained by the SMI was significantly correlated with self reported migraine (Spearman’s rho = 0.16, p = 0.001). In a study of self recognition of migraine, Lipton et al (Neurology 2002, 58 s21-26) reported that individuals who reported that they had migraine were 3 times more likely to meet the ICHD criteria for migraine. Background R. The sentence “An even smaller fraction.....” gives a wrong impression. The majority of migraineurs have very few attacks per year, while only a few percent have frequent attacks that might qualify for prophylactic treatment. However, after the introduction of the triptans in the 90ies the need for prophylactic has changed, as many migraineurs have excellent effect of a triptan and does not necessarily need prophylactic treatment even if they have many attacks. The authors need to consult ref. 13 which encompasses frequency of migraine attacks. A. In this sentence we are trying to highlight the nature of migraine underrecognition and undertreatment. Triptans did indeed offer a great relief from acute migraine headache. However, the response rate to triptans varied from 44-70% and only Sumatriptan s.c. administration achieved 80% response rate (Saxena et al 2006). In addition, triptans are expensive and not all patients have access to them. In a large population study of US households, only 20% of migraine sufferers used prescription treatment for acute migraine (Diamond et al 2006). Migraine attacks were reported to occur at a rate of more than 3 per month in 31.3% of migrainerurs and over half of migraineurs reported severe impairment. Over a quarter met the