Exploratory and confirmatory factor analysis of the Persian version of the low-vision quality-of-life questionnaire

Abstract

Most of the vision quality assessment questionnaires are in English. None of the low-vision-related quality-of-life questionnaires have been translated or developed in Persian. It will help Persian optometrists and ophthalmologists to assess improvement of visual function and quality of life during their low-vision rehabilitation programs. In this study, we aimed to translate the low-vision quality-of-life (LVQOL) questionnaire in Persian language and apply exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) to assess the construct validity and fit model. Translation and cultural adjustment of the English language LVQOL questionnaire to Persian was undertaken. Overall, 100 low-vision patients were participated to validate and model the assessment questionnaire by both EFA and CFA methods. Complementary EFA and CFA results provide detailed information about item and scale performance of the Persian LVQOL. EFA showed Items 15, 16, and 21 which had factor loadings lower than 0.3. The modified model had the comparative fit index (CFI) and root mean square error of approximation (RMSEA) of 0.89 and 0.06, respectively. The translation, adjustment, and fit analysis of the LVQOL questionnaire into Persian were successful and it will be valuable in both clinical practice and research.