Purpose. To report on the development and validation of a short form of the Contact Lens Dry Eye Questionnaire (the CLDEQ-8) to enable it to reflect status of and change in overall opinion (“opinion”) of soft contact lenses (SCLs).
Methods. Item reduction for the CLDEQ was achieved by correlation with overall opinion of SCLs at follow-up visits in a sample of 38 SCL wearers at one academic clinical site. The CLDEQ-8 score (frequency plus late day intensity of dryness, discomfort, and “blurry vision”; frequency of “closing eyes to rest them” and “removing CLs to relieve discomfort”) was then tested in 379 SCL wearers in a multicenter study with analysis stratified by opinion ratings at baseline and 2 weeks postrandomization to new silicone hydrogel SCLs. The sum of CLDEQ-8 scores (maximum 37) was correlated with opinion by Spearman's rank correlation coefficient and analyzed for change in opinion by analysis of variance (ANOVA).
Results. The CLDEQ-8 scores in the validation sample were highly correlated with habitual baseline opinion (−0.44, p < 0.0001) and responsive to change in opinion postrandomization (−0.58, p < 0.0001). Baseline CLDEQ-8 scores by opinion status were as follows: Fair: 17.4 ± 8.7, Good 13.7 ± 6.4, Very Good 9.1 ± 4.7, and Excellent 6.4 ± 3.7 (ANOVA, F = 291.1, p < 0.0001). After 2 weeks, change in CLDEQ-8 scores by improvement status was as follows: Much Improved: −16.7 ± 10.0, Unchanged: −2.3 ± 5.0, to Much Worse +8.5 ± 5.8 (ANOVA, F = 16.5, p < 0.001).
Conclusions. The CLDEQ-8 score significantly reflected baseline status and change in overall opinion after refitting with two types of silicone hydrogels. The CLDEQ-8 score is a valid outcome measure in SCL clinical trials to reflect opinion of SCLs.
†OD, MS, FAAO
‡BSc(Hons), MCOptom, FAAO
Clinical Trial Consultant, Atlanta, Georgia (RLC), Indiana University School of Optometry, Bloomington, Indiana (CGB), and Johnson & Johnson Vision Care, Inc., Jacksonville, Florida (KM, SBH-C).
Received March 5, 2012; accepted June 6, 2012.
Robin L. Chalmers Clinical Trial Consultant 2097 East Lake Road Atlanta, Georgia 30307 e-mail: Chalmers2097@gmail.com