The modified DYMUS questionnaire is a reliable, valid and easy‐to‐use tool in the assessment of dysphagia in multiple sclerosis

Abstract

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. The objective was to investigate the psychometric properties of the Dysphagia in Multiple Sclerosis (DYMUS) questionnaire and examine whether item reduction improves them. 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, and item reduction, reliability, validity analysis and normative data generation for the modified DYMUS (mod-DYMUS). 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 and 3-7) showed 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 indicates dysphagia. 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 patients' needs.