Diagnosis of migrainous vertigo: validity of a structured interview

Migraine and vestibular symptoms are co-morbid. Migraine is increasingly recognized as a cause of benign, recurrent vertigo. Although the International Headache Society does not currently include the diagnosis of migrainous vertigo, specific criteria have been proposed and utilized in clinical trials.

Seventeen adult migraineurs were separately screened for the diagnosis of migrainous vertigo using a standardized structured interview for migrainous vertigo (SIM-V) and a clinical evaluation by an experienced neurotologist. The SIM-V was administered by a nurse who read and recorded subject responses, obtaining no additional information for the diagnosis of migrainous vertigo. Comparison of diagnoses between clinician and SIM-V was made using Cohen's kappa reliability testing. Subjects were asked to return for a second interview by the same nurse using the SIM-V, at least 2 weeks after the initial assessment. Testing stability was evaluated by comparing diagnoses obtained with each SIM-V administration.

Cohen's kappa demonstrated excellent test validity (kappa=0.75). Fourteen subjects returned for repeat testing, with excellent retest stability (kappa=0.85). The additional three subjects could not be relocated or were not interested in attending a retest appointment.

The SIM-V is an easy-to-administer screening tool for the diagnosis of migrainous vertigo. Diagnostic comparison to a standard clinical assessment shows good test validity. Retest stability was also demonstrated. The SIM-V may be a useful screening tool for migraineurs with an additional complaint of dizziness.