The Opternative exam is a bit different than sitting down in an eye doctor's office and squinting to read a chart of letters. First of all, the online test requires you to use both your smartphone, ...

Assessment of visual acuity (VA) has been shown to vary between tests, which may be attributable in part to test inaccuracies, such as a change in the distance between the chart and subject. Therefore ...

Smartphone-based Snellen visual acuity charts has become popularized; however, their accuracy has not been established. This study aimed to evaluate the equivalence of a smartphone-based visual acuity ...