Real-life, observational, single-center cohort study to describe the efficacy of prophylactic treatment in patients after failure of at least 2 prophylactic treatments. Patients included in the study will be followed up in consultations or day hospitals according to their usual care, and will be asked to complete the MIDAS, HIT-6, PGIC, HAD and WPAI questionnaires at each visit. Data describing their care will be extracted from computerized patient records.

Using HIT-6 (Headache Impact Test short-form) questionnaire which addresses six main domains affected by headaches, including pain, social functioning, role functioning, cognitive functioning, vitality and psychological stress. This survey is extremely useful for screening and monitoring how headaches affect patients in their day-to-day lives over time.

Each item is answered on a 5-point Likert scale (6 = never, 8 = rarely, 10 = sometimes, 11 = very often, 13 = always). The scoring of the HIT-6 was derived to approximate the total score obtained from a larger battery of items, using results from item response theory (IRT) [10]. The final score is obtained from simple summation of the six items.

MIDAS scale (Migraine Disability Assessment) measures headache-related disability and improve doctor-patient communication about the functional consequences of migraine. The questionnaire was based on five disability questions that focus on lost time in three domains: schoolwork or work for pay; household work or chores; and family, social, and leisure activities.

This instrument is scored as follows: 5 to 10 indicates little or no disability, 10 to 20 indicates moderate disability, and higher than 20 denotes severe disability.