JMIR Publications

ABSTRACT

Background:

Digital tools provide a unique opportunity to increase access to eye care. We developed an online test that measures visual acuity and both spherical and cylindrical refractive errors. This test is CE-marked and available at easee.online. The purpose of this study was to compare the efficacy of this online tool with traditional manifest subjective refraction in a prospective open-label non-inferiority clinical trial.

Objective:

Evaluate the outcome of an online refraction compared to a manifest refraction (golden standard)

Methods:

Healthy volunteers 18-40 years of age with a refraction error between -6 and +4 diopters (D) were eligible. Each participant performed the online test, and the reference test was performed by an optometrist. An absolute difference in refractive error of <0.5 D was considered non-inferior. Reliability was assessed using an intraclass correlation coefficient (ICC). Both uncorrected and corrected visual acuity were measured.

Results:

Two-hundred eyes in 100 healthy volunteers were examined. The online assessment of refractive error had excellent correlation with the reference test (ICC =0.92) and was considered non-inferior to the reference test. Uncorrected visual acuity was similar with the online test and the reference test (P=.21). Visual acuity was significantly improved using the prescription obtained using the online tool (P<.01). The online test provided the best results in participants with mild myopia (i.e. less than 3D), with a mean difference of 0.02±0.49 D (P=.48) and yielding a corrected visual acuity of >1.0 in 90% of participants.

Conclusions:

Our results indicate that online eye testing is a valid and safe method for measuring visual acuity and refractive error in healthy eyes, particularly for mild myopia. This tool can be used for screening purposes and is an easily accessible alternative to the subjective manifest refraction test. Clinical Trial: NCT03313921