Assessment of Utility in Migraine: Mapping the Migraine-Specific Questionnaire to the EQ-5D-5L

Introduction: There are increasing demands for studies of cost-effectiveness to allocate resources for disease prevention and treatment strategies. The aim of this study is to measure quality of life in migraineurs, based on the Migraine-Specific Questionnaire (MSQ) and EQ-5D-5L, and thereafter map an algorithm to estimate health-state utility values from the MSQ in individuals with migraine. Methods: In this cross-sectional study conducted between May and July 2018 in a tertiary headache clinic in Tehran, Iran, migraineurs diagnosed based on International Classification of Headache Disorders (ICHD)-3b were enrolled and were asked to complete the MSQ questionnaire and EQ-5D questionnaire. The Spearman correlation coefficient (r) was calculated to measure the correlation between the EQ-5D-5L and MSQ v2.1 domains' score. A P value of <.05 was considered statistically significant. After statistical analysis, several regression models were presented to map the results of the MSQ domains to the utility index, and the preferred model was achieved based on goodness of fit and the model's predictive performance. Results: The preferred MSQ algorithm had approximately the same prediction errors in all migraineurs, episodic and chronic migraine (root mean square error 0.24, 0.24, and 0.23, respectively). The preferred MSQ model explained a variance of 0.26 (R2) in episodic and 0.38 in chronic migraine in the EQ-5D-5L questionnaire. Conclusion: The preferred MSQ mapping algorithm will be suitable in estimating health state utilities in trials of patients with migraine that contain MSQ scores but lack utility values.