How are eye vision test generally scored?

Compared to standard: The chart used to test the eye is calibrated for normal vision at 20 feet. The outcome achieved is compared to what a normal eye can see at 20 feet. So if you can only see at 20 feet what a normal eye sees at 40 feet, your vision is considered to be 20/40. This is measured with and without corrective lenses at distance and at near. The vision with correction is considered to show the true vision.

Eye chart: Vision is recorded by the smallest line read on the vision chart in reference to 20/20 being normal, and it is recorded with and without your best correction.