Fig. 1

Audit design flowchart. 125 patients who met the ICHD definition of chronic migraine, had failed and/or had contraindications to ≥2 classes of preventative medications, and had a previous unsatisfactory response to BoNTA were selected for the audit. 19 patients did not attend the training day or opted out of the audit prior to the first injection. A total of 106 patients received at least one dose of erenumab. 8 patients who did not submit at least one month of pre- or post-treatment data were excluded from the analysis