The modified-DYMUS Questionnaire is a reliable, valid and easy-to-use tool in the assessment of dysphagia in Multiple Sclerosis.

BACKGROUND: Many patients with multiple sclerosis (MS) present swallowing difficulties. Dysphagia is associated with significant morbidity and mortality, has a profound impact on the quality of life but is under-reported by patients.

OBJECTIVE: To investigate the psychometric properties of the Dysphagia in Multiple Sclerosis (DYMUS) questionnaire, and examine whether item reduction is improving them.

METHODS: The participants, 153 patients with MS, and 104 healthy controls, completed the DYMUS and the Eating Assessment Tool-10 (EAT-10). The study consisted of factor, reliability, and validity analysis of DYMUS, item reduction, reliability, validity analysis, and normative data generation for the modified DYMUS (mod-DYMUS).

RESULTS: The internal consistency of DYMUS was excellent (Cronbach's alpha: 0.886). Test-retest reliability was good for all the items. Factor and reliability analysis, along with other psychometric features, supported item reduction. The mod-DYMUS (consisting of items 1, 3-7) has shown improved internal consistency (Cronbach's alpha: 0.903), and inter-item correlation coefficients (0.558-0.657), good test-retest reliability, excellent criterion validity, and improved convergent validity. Patients had significantly higher mean mod-DYMUS score than controls (p<0.001), and dysphagic patients (EAT-10≥3) had significantly higher mod-DYMUS than non-dysphagic patients (p<0.001). A strong positive and significant correlation was noted between the mod-DYMUS and the EAT-10 (p<0.001). A mod-DYMUS score of 1 or higher is indicating dysphagia.

CONCLUSIONS: Item reduction improves the psychometric properties of DYMUS. The mod-DYMUS, is a valid, reliable, low-burden, screening tool for the detection of dysphagia in MS, which can enhance personalized assessment and guide management decisions that better respond to individual patient's needs.