Cross-cultural adaptation and psychometric evaluation of VADL-M-Marathi version of the Vestibular Disorders Activities of Daily Living Scale: a modified Delphi study

Abstract Background Vestibular disorders can significantly impact individuals’ ability to perform daily activities. Reliable assessment tools in native languages are essential for accurate evaluation and effective intervention. Objectives This study aimed to translate, culturally adapt, and evaluate the psychometric properties of the Marathi version of the Vestibular Disorders Activities of Daily Living Scale, ensuring its suitability for Marathi-speaking individuals with vestibular disorders. Specifically, it sought to ensure that VADL-M is culturally appropriate, easy to understand, and accurately measures functional limitations in daily activities for people with vestibular disorders. The study also examined how VADL-M scores relate to dizziness symptoms measured by the Dizziness Symptom Profile (DSP). Methods The VADL scale was translated and culturally adapted using a modified Delphi methodology to ensure linguistic and cultural appropriateness. A two- round Delphi method was applied: in round 1, four professionals evaluated the scale’s content; in round 2, 50 patients with vestibular pathologies used the VADL-M scale and Dizziness Symptom Profile (DSP) to analyze concurrent validity, internal consistency, test-retest reliability, and split-half reliability using SPSS v25. Results The translation and adaptation process involved forward translation, back-translation, expert review, and iterative revisions. The Delphi panel included experienced professionals in audiology and vestibular care, as well as Marathi-speaking individuals diagnosed with vestibular disorders. The adapted scale demonstrated strong psychometric properties. Internal consistency was excellent, with a Cronbach’s alpha of 0.919. Test-retest reliability was high, with an intraclass correlation coefficient of 0.921, indicating stability over time. Concurrent validity, assessed against a standardized dizziness-related questionnaire, showed a strong correlation (rho = 0.759), confirming the scale’s relevance. The content validity index was 0.884, supporting the clarity, cultural sensitivity, and relevance of the items. Additionally, a large effect size (Cohen’s D = −1.142) highlighted the tool’s sensitivity in detecting impairments in daily activities among individuals with vestibular disorders. Conclusions The Marathi version of the Vestibular Disorders Activities of Daily Living Scale is a valid and reliable instrument for assessing functional limitations in Marathi-speaking individuals with vestibular disorders. The use of the Delphi method contributed to its cultural and contextual relevance. This patient-centered tool can enhance clinical assessments, guide rehabilitation strategies, and support research involving native language speakers in diverse settings.