Importance of quantifying migraine disability in the native language of the migraineur

In their ranking of causes of disability, migraine is listed among the top 5 most disabling conditions by the World Health Organization [1]. Therefore, migraine is associated with a high impact on society and public health, not only through its limitation of working capacity, but also in social and leisure activities [2]. Yet migraine has “1,000 faces,” implying a broad bandwidth of clinical presentations, from patients who have the occasional headache attack to patients suffering from daily headaches. There is a correlation between the frequency of headaches and grade of disability [3], whereby meaningful disability starts at frequencies of higher than 3 days per month.

Several instruments measuring the disease-specific disability and impact on quality of life have been developed [4]. Especially with new emerging, but also more expensive treatments, there is a need to select patients suitable for these treatments [5]. One of the most frequently used scales, the Migraine Disability Assessment (MIDAS) Questionnaire, was originally developed to assess migraine-related disability in the triptan era [6]. While MIDAS is a short and relatively easy questionnaire with 7 items, it not only focuses on days with complete loss of working capacity (“absenteeism”), but also includes days with a reduced productivity (“presenteeism”) over the past 90 days. Presenteeism is especially high among patients with migraine and contributes to indirect costs that are difficult to objectify [7]. Of course, scores and questionnaires will never be capable of quantifying the burden of a disease adequately. However, the availability of a questionnaire in the native language of a patient will always contribute to a better understanding of the patient's disease. Reliability and validity of the MIDAS questionnaire have been established and tested in various countries and languages. In this issue, Asawavichienjinda et al. report testing of a Thai version of the MIDAS Questionnaire for validity, test–retest reliability, and internal consistency [8].