The Translation and Psychometric Evaluation of the Persian Version of the Neuropsychological Vertigo Inventory

Background and Aim: Experiencing dizziness/vertigo is often an indication of dysfunction in the vestibular system. Recent findings show a connection between peripheral vestibular dysfunction and cognitive impairments. The Neuropsychological Vertigo Inventory (NVI) can assess physical, emotional, and cognitive issues in individuals with dizziness/vertigo. The aim of this research was to translate, cultural adaptation and evaluation of the reliability and validity of NVI to Persian. Methods: In this descriptive-analytical study, the NVI scale was translated and adapted to the Iranian cultural context following the international quality of life assessment protocol for translation and equivalence. After obtaining face validity, the scale was administered to 140 patients with peripheral vestibular system dysfunction and 70 control group (age between 25 and 80 years). After one week, 50 participants were asked to complete the questionnaire again. Eventually, reliability was evaluated with both methods of internal consistency and test-retest reproducibility. Results: Out of the 28 items in the NVI scale, 3 items were modified to better align with the cultural conditions of Iranians. The impact scores for most items in this scale were found to be higher than 1.5. The Cronbach’s alpha coefficient values for the overall scale (0.90) and test-retest reliability with intra-class correlation coefficient for the overall scale (0.91) were confirmed. Conclusion: The Persian version of NVI scale demonstrates excellent validity and reliability, and it exhibits a high level of content alignment with the original version. Therefore, it can be a useful tool to better understand the physical, emotional and cognitive disturbances in patients with vertigo/dizziness.   Keywords: Validity; reliability; dizziness; vertigo; vestibular dysfunction; neuropsychological vertigo inventory