Objectives.-To compare the interviewer-administered Quality, of Well-being Scale (QWB) with a self-administered Form (QWB-SA) for patients with migraine, and to compare the health status of migraineurs to other medical populations. Background.-With the increasing need to document the cost-effectiveness of treatment for migraine, limitations with both the Medical Outcomes Study Short Form-36 items and the QWB have been an impediment to research using cost-effectiveness as an outcome. Demonstrating the sensitivity of an alternative instrument which addresses these limitations would facilitate cost-effectiveness analyses on treatments for migraine. Methods.-Eighty-nine adults (87% women) known to suffer from migraine were asked to complete both the interviewer-administered QWB and the self-administered version (QWB-SA) on three occasions. The first occasion was on a day when no migraine was experienced in the previous 7 days. The second and third assessments were completed within 48 hours of the onset of a migraine. Results.-While both the QWB and the QWB-SA successfully distinguished migraine from nonmigraine days, more migraines mere reported on the QWB-SA. Overall, both instruments showed similar patterns of patient dysfunction during a migraine attack. Each component of the QWB-SA successfully distinguished migraine from nonmigraine days, and the QWB-SA showed a linear sensitivity to pain intensity and disability during a migraine episode, Both instruments are able to detect a migraine's effect on multiple domains of quality of life. Study participants scored significantly lower on the QWB-SA during a migraine episode than several comparison medical populations. Conclusions.-The QWB and the QWB-SA appear to have sensitivity to migraine severity, and the ability to quantitate an effect in multiple quality-of-life domains. Both measures can be used to calculate quality-adjusted Life-years, thus facilitating cost-effectiveness and health policy work in this important clinical area.