Minimal important change and responsiveness of the Migraine Disability Assessment Score (MIDAS) questionnaire

BACKGROUND: The MIDAS is the most used questionnaire to evaluate migraine-related disability, but its utility to assess treatment response remains unclear. Our aim was to estimate the MIDAS’ minimal important change (MIC) value and its responsiveness. METHODS: A total of 103 patients were enrolled in a non-pharmacological, preference-based clinical trial. MIDAS and global rating of self-perceived change (GRoC) scores were collected at baseline, after 5 weeks of treatment, 4-weeks and 3-months follow-up after treatment. Anchor-based approaches were used to establish MIC values and responsiveness. FINDINGS: In all 3 timepoint comparisons, MIDAS presented a MIC of 4.5 points. A moderate positive correlation was identified between the MIDAS change and GRoC scores. The area under the curve ranged from 0.63 to 0.68. CONCLUSIONS: This study showed that MIDAS has a limited responsiveness to change. A change of 4.5 points or more represents a clinically important change for patients with high frequent migraine and chronic migraine receiving non-pharmacological treatment.