Stability, responsiveness, and reproducibility of a visual analog scale for treatment satisfaction in migraine
Headache: The Journal of Head and Face Pain, 05/14/2012
Lucas C et al. – The visual analog scale (VAS) scale described here is a responsive and easy–to–use tool for evaluating treatment satisfaction and for monitoring changes to treatment if these are required.
Methods- The study used an open–label, multicenter, prospective design.
- Adult patients fulfilling diagnostic criteria for migraine and who consulted a participating hospital or community neurology clinic were eligible.
- At inclusion, patients rated their satisfaction with their current treatment on the VAS.
- Those scoring 7–10 (satisfied) on the VAS were allocated to the VASCO cohort, and those scoring 0–4 (dissatisfied) were switched to almotriptan and allocated to the ALMO cohort.
- Patients scoring between 4 and 7 were assigned to 1 or other cohort at the physician's discretion.
- The VAS was re–administered at home the next day and also after the treatment of 3 further headaches, both at home and at a follow–up visit.
- 98 patients in the VASCO cohort and 102 in the ALMO cohort were analyzed.
- Stability was evaluated in the VASCO cohort: 55/98 patients initially satisfied with treatment remained so at study end, whereas 7/98 became dissatisfied.
- Responsiveness of the VAS to a change in treatment was evaluated in the ALMO cohort: 64/102 patients moved to a higher treatment satisfaction category, whereas 6/102 moved to a lower one.
- Reproducibility of the VAS was determined in 4 settings (both at the inclusion visit and at study closure in both cohorts).
- In each setting, VAS scores were compared between consultation and at–home ratings.
- In 3 of the 4 settings (both measures in the ALMO cohort and at study closure in the VASCO cohort), good agreement was observed between the 2 ratings (κ = 0.62–0.69).
- At inclusion in the VASCO cohort, agreement was only fair (κ = 0.33).
