Inclusion Criteria:  General Cohort  Adult (18 years or older) Newly initiating on Aimovig (no other claims during a 180-day wash-in period) Had continuous medical and pharmacy benefit eligibility from 180 days pre-index of Aimovig through 180-days post-index  Primary & Secondary Objectives Sub-Cohort  - Had 3 consecutive months with a claim for Aimovig (≤15 days gap between days supply and the subsequent claim to be considered consecutive)  Primary & Secondary Objectives Cost Sensitivity Analyses Sub-Cohorts  Had continuous medical and pharmacy benefit eligibility from 180 days pre-index of Aimovig through 270-days post-index to permit assessment of cost outcomes (all-cause and migraine-related) during days 91-270 post-index Had continuous medical and pharmacy benefit eligibility from 180 days pre-index of Aimovig to the maximum follow-up time post-index with continuous medical and prescription insurance eligibility until the data end date (September 1, 2019)  Exclusion Criteria:  Patients with any claim for another CGRP-targeted medication (Ajovy or Emgality) during entire study period