The study also has limitations worth knowing. Migraine classification was based on participants’ recall of a clinician diagnosis, which means some people with migraine may have been misclassified as not having it, likely leading to an underestimate of any true association. The age at which participants were diagnosed with migraine was not captured, so researchers couldn’t distinguish between a recent diagnosis and a long history of the condition. And while the study adjusted for a wide range of stroke risk factors, other variables (like migraine frequency, alcohol use, or hormone replacement therapy) were not accounted for.
