The client’s vision is tested with a Snellen chart. The results of the tests are documented as 20/60. The nurse interprets this as:
A. The client can read at a distance of 60 feet what a client with normal vision can read at 20 feet.
B. The client is legally blind.
C. The client’s vision is normal.
D. The client can read only at a distance of 20 feet what a client with normal vision can read at 60 feet.
Correct Answer: D. The client can read only at a distance of 20 feet what a client with normal vision can read at 60 feet.
Vision that is 20/20 is normal, that is, the client is able to read from 20 feet what a person with normal vision can read from 20 feet. A client with a visual acuity of 20/60 only can read at a distance of 20 feet of what a person with normal vision can read at 60 feet. The results of visual acuity are classically reported using 20/20 (6/6 when using meters) for standard vision. The numerator describes the distance from the chart, typically 20 ft (6 m). The denominator describes the distance that an individual with normal vision (20/20 vision) can read the same line on the chart.
Option A: An individual with 20/60 vision would be able to distinguish the same optotype at 20 ft that another individual with normal (20/20) vision distinguishes at 60 ft. In the logMAR, visual acuity is reported as a single number where 0.0 is standard vision.
Option B: The WHO describes individuals with low vision as having a best-corrected vision of 20/60 or worse, and blind as best corrected vision worse than 20/400, whereas legal blindness is identified as 20/200 in the United States.
Option C: Although 20/20 visual acuity has been referred to as “perfect vision,” it is important to remember that this is only one aspect of vision and does not include other elements such as depth perception, peripheral vision, and colorblindness.
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