A Double-Masked Randomized Crossover Trial Investigating the Efficacy of Colored Spectacle Lenses in Adults with Visual Stress: Protocol and Baseline Findings

Purpose : Uncertainty exists about the efficacy of colored spectacle lenses in the treatment of reading difficulty for those with visual stress. This study is a double-masked placebo-controlled randomized crossover superiority trial to test whether colored lenses improve reading speed and performance, and reduce discomfort in symptomatic adult readers.

Methods : 1377 adult undergraduate students were screened for presence of visual stress using a reading symptom questionnaire and presence of ‘pattern glare’ with a mid-spatial frequency pattern glare test. 213 participants were identified with significant symptoms and/or pattern glare and were invited to baseline screening. Eligible participants wore colored spectacles with optimal and control tints (determined by Intuitive Colorimetry™), in a randomized 1:1 crossover control, each for a 6-week period followed by a 2-week wash-out. Control lens color fell outside the beneficial effect identified by participants for optimal lenses but was not aversive. Reading aloud speed (Wilkins Rate of Reading Test, WRRT) and reading symptoms (symptom questionnaire) were measured at baseline and with both sets of colored lenses during the trial. Upon trial completion participants were asked which coloured lens was most beneficial in a ‘head-to-head’ comparison. Long-term spectacle wear compliance was explored in a 3-month follow-up.

Results : 60 participants who volunteered to attend for baseline screening met trial inclusion criteria (6M:51F:3N, aged 20.8±3.8 years). Mean±SD reading speed (WRRT) showed reduced performance at baseline (134.6±30.4 words per minute; one-sample t-test t(59)=34.0, p<0.001) compared to previously reported values for undergraduate readers (171.3±17.1 words per minute). Raised pattern glare scores were noted (Median=4, range 0-7), with diagnosable pattern glare (pattern glare test scores >3) present in 95% (n=57) of participants. The most frequently reported symptoms were ‘repeating words’ (90%), ‘skipping words’ (85%) and ‘losing place’ (88%) when reading.

Conclusions : This trial will determine if ideally-tinted colored lenses are superior to control lenses at easing symptoms and improving reading speed in adults with visual stress. Baseline characteristics show reduced reading speed in the cohort compared to asymptomatic adult readers.

This abstract was presented at the 2025 ARVO Annual Meeting, held in Salt Lake City, Utah, May 4-8, 2025.