Translation and validation of the contact lens dry eye questionnaire 8 (CLDEQ-8) in Canadian French

To present the process that led to the creation of the French Canadian translated version of the Contact Lens Dry Eye Questionnaire-8 (which allows for an assessment of symptoms while wearing soft contact lenses) as well as the validation data of the f-CLDEQ-8.

The CLDEQ-8 went through the process of reverse translation, which was then reviewed and improved by an experts' committee to create a first version of the French questionnaire. Cognitive interviews were conducted to pretest the tool and ensure content validity. After a review of the pretest, the f-CLDEQ-8 was created. A web-based version of this questionnaire was sent to contact lens wearers (CLW) recruited out of a clinical setting for completion at two different endpoints interspaced by 7 days. Internal consistency and test-reliability were calculated using Cronbach's alpha and Intra-class Correlation coefficient (ICC), respectively. Convergent validity between the f-CLDEQ-8 score and overall opinion of the contact lenses was evaluated with a correlation.

9 CLW with different socio-economic statuses and education levels went through a cognitive interview with the back-translated version of the f-CLDEQ-8 to improve the questionnaire wording and enhance its comprehension. 63 CLW (34.2 ± 10.1 years old and 2/3 of them women) completed the f-CLDEQ-8 twice. An average Cronbach alpha of 0.928 was found and an ICC of 0.944 (CI at 95 % 0.905;0.966). A moderately strong correlation of -0.714 (CI at 95 % -0.817;-0.566) was found between the overall opinion of the contact lenses and the total score to the f-CLDEQ-8.

The French language version (f-CLDEQ-8) generated from the original CLDEQ -8 was shown to be easy to use, reliable and culturally adapted to French spoken in Canada.