PURPOSE: To translate and test the reliability and validity of a Persian translation of the Refractive Status and Vision Profile (RSVP), a vision-related quality of life questionnaire, in Iran. METHODS: Forward & backward translation, committee review and pilot testing were performed to develop a final Iranian version of the RSVP. Seventy-three consecutive patients with refractive error before or after refractive surgery at the LASIK ward of Farabi Eye Hospital completed the questionnaire. A convenience sample of 14 patients completed the questionnaire twice within one week. Reliability was measured by internal consistency (Cronbach's alpha) and the intraclass correlation coefficient for test-retest reliability. Validity was evaluated by correlation between the different RSVP subscales, known groups comparison analysis, and correlation between the subscales versus global items and traditional clinical measures. RESULTS: Internal consistency was high (Cronbach's alpha : 0.71-0.92; except for the subscale expectations, alpha : 0.6). Test-retest reliability of subscales and the overall RSVP scale, as estimated by the intraclass correlation coefficient, was high except for optical problems and glare. Comparisons between pre- and post-operative groups of patients showed significantly higher (worse) scores for concern, physical/social functioning, and the overall score in the pre-operative group. Almost all subscales showed desirable inter-scale correlations. CONCLUSION: The Iranian version of the RSVP is a reliable and valid measure of vision-related quality of life in patients with refractive error.
PURPOSE: To translate and test the reliability and validity of a Persian translation of the Refractive Status and Vision Profile (RSVP), a vision-related quality of life questionnaire, in Iran. METHODS: Forward & backward translation, committee review and pilot testing were performed to develop a final Iranian version of the RSVP. Seventy-three consecutive patients with refractive error before or after refractive surgery at the LASIK ward of Farabi Eye Hospital completed the questionnaire. A convenience sample of 14 patients completed the questionnaire twice within one week. Reliability was measured by internal consistency (Cronbach's alpha) and the intraclass correlation coefficient for test-retest reliability. Validity was evaluated by correlation between the different RSVP subscales, known groups comparison analysis, and correlation between the subscales versus global items and traditional clinical measures. RESULTS: Internal consistency was high (Cronbach's alpha : 0.71-0.92; except for the subscale expectations, alpha : 0.6). Test-retest reliability of subscales and the overall RSVP scale, as estimated by the intraclass correlation coefficient, was high except for optical problems and glare. Comparisons between pre- and post-operative groups of patients showed significantly higher (worse) scores for concern, physical/social functioning, and the overall score in the pre-operative group. Almost all subscales showed desirable inter-scale correlations. CONCLUSION: The Iranian version of the RSVP is a reliable and valid measure of vision-related quality of life in patients with refractive error.