Cross-cultural adaptation, reliability, and validity of the Persian version of the overactive bladder questionnaire (OAB-V8)

Background and objectives: Overactive bladder (OAB) is characterized by urinary frequency and is recognized as a disorder. Various tools are available for diagnosing this condition. This study aimed to evaluate the reliability and validity of the Persian version of the 8-item Overactive Bladder Scale (OAB-V8). Methods: This analytical cross-sectional study was conducted on a sample of 150 OAB patients. The OAB-V8 scale was translated and culturally adapted following established guidelines. Face and content validity were assessed using the Impact Score (IS), Content Validity Index (CVI), and Content Validity Ratio (CVR) indices. Reliability was evaluated by calculating Cronbach's alpha (alpha) and utilizing the test-retest method (Intra-class correlation coefficients (ICC)). Construct validity was explored through exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). All statistical analyses were carried out using SPSS version 24 and AMOS version 24, with a significance level set at 5 %. Results: The face validity was confirmed, with all items having an IS value greater than 1.5. Content validity was also confirmed, as most items had a Content Validity Index (CVI) higher than 0.79, and the average Content Validity Ratio (CVR) value was 0.96. In the initial phase of Exploratory Factor Analysis (EFA), the sample adequacy and suitability of the exploratory analysis were confirmed (Kaiser-Meyer-Olkin (KMO) test value = 0.784, Bartlett's Test p-value <0.05). Two dimensions explaining 61.87 % of the variance were then extracted. In the Confirmatory Factor Analysis (CFA), the fit indices were deemed acceptable (chi<^>2/df = 2.006, CFI = 0.96, GFI = 0.95, AGFI = 0.89, TLI = 0.93, RMSEA = 0.08). The reliability was confirmed with an alpha coefficient of 0.81 and an Intraclass Correlation Coefficient (ICC) of 0.98. Conclusion: The Persian version of the OAB-V8 questionnaire demonstrated good validity and reliability, indicating its suitability for use in Persian-speaking countries.