MSQ - MIGRAINE-SPECIFIC QUALITY-OF-LIFE QUESTIONNAIRE - FURTHER INVESTIGATION OF THE FACTOR STRUCTURE

MSQ, the 16-item Migraine-Specific Quality-of-Life Questionnaire (Vers ion 1.0), was developed by Glare Wellcome Inc. to assess the effect of migraine and its treatment on patients' health-related quality of lif e (HR-QOL). The MSQ was hypothesised to measure 3 meaningful dimension s: (i) Role Function-Restrictive; (ii) Role Function-Preventive; and ( iii) Emotional Function. The objective of this research was to further investigate the number of dimensions as well as the items contained i n each dimension through principal components factor analysis of clini cal trial data. Secondary objectives were to determine whether the fac tor structure changed in post-treatment visits compared with screening visits, to make recommendations for coding the MSQ when the patient d id not have a migraine in the previous 4 weeks, and to modify the MSQ if so indicated by this research. Results supported the existence of 3 distinct factors which agreed strongly with the hypothesised dimensio ns. The analysis of post-treatment data suggested that the underlying factor structure of the MSQ varies as a result of treatment. Based on evaluations of the 'did not have a migraine' response, it was conclude d that it be dropped from the MSQ. All these changes have been incorpo rated into MSQ (Version 2.0) which is being evaluated in studies to de termine if its psychometric properties are different than the properti es of the previous version.