Validation of the Ocular Surface Disease Index Questionnaire for Chilean patients

Background: Ocular Surface Disease Index (OSDI) is the most commonly used questionnaire worldwide to detect dry eye disease. Although it is massively used in clinical practice in Chile, its use has not been validated yet in the country. Aim: To develop a cultural adaptation and to validate the OSDI questionnaire for the Chilean population. Material and Methods: For cultural adaptation, a translation, retro-translation and an expert panel review was carried out. The resulting questionnaire was applied to a pilot group of twelve participants and their comments were considered for the final questionnaire version. The final questionnaire was applied to a non-random sample of 200 patients aged 53 +/- 17 years (75% women). Internal consistency and construct validity were evaluated by Cronbach's alpha and exploratory factor analysis respectively. Results: According to the OSDI score, 81% of respondents had dry eye (55% severe). Reliability was 0.91 and factor analysis resulted in three factors explaining 75.4% of the total variance. Conclusions: The OSDI questionnaire version obtained in this study demonstrated excellent internal consistency values and adequate construct validity making it applicable to clinical practice and dry eye research.