Direct Access to MRI and Neurology Referrals for the Management of Patients With Chronic Headache.

Inclusion Criteria: * Every patient aged 16 years or over with: i) chronic headache as a primary cause that has lasted ≥ 15 days per month for more than 3 months; and ii) referred from GP practices to GSTT, either directly referred to an MRI exam or a Neurology outpatient appointment. Exclusion Criteria: * Children under the age of 16; * Patients with red flags as defined in NICE guideline CG150; * Patients without chronic primary headache, i.e. a headache that has not persisted for ≥ 15 days per month for more than 3 months * Patients with headache referred through the two week wait list; * Patients who lack capacity to give consent or participate in the study; * Patients not fluent in English; * Prisoners; * Patients that are already taking part in a clinical trial of an investigational medicinal products (CTIMPs).