Vision Screenings vs Eye Exams: Key Differences

What is a vision screening?

A vision screening is a short exam designed to identify long distance vision issues. Schools may provide periodic vision screenings for their students, and are often part of local health fairs put on by hospitals and social service agencies. When you apply for a driver's license, the DMV may also perform a short screening to determine if you need glasses for driving.

Is a vision screening a substitute for an actual eye exam?

No - A vision screening's usefulness is limited by its tendency to miss more than they find. In fact, they may create a false sense of security for those who "pass" the screening but have underlying issues. Because a false sense of security makes them less likely to see a licensed optometrist or ophthalmologist, these conditions often worsen without treatment. Additionally, a vision screening, even performed by a primary care physician, often lacks the equipment required to undergo a thorough evaluation of eye health.

What can a vision screening miss?

While a vision screening may detect that there is an issue with your vision, it cannot diagnose diseases that may be causing it. Also, because vision screenings tend to only measure long distance visual acuity, it will not measure how your eyes function up close or together, nor can it diagnose disease within structures of the eye.

What does an eye exam cover that a screening does not?

• Your optometrist or ophthalmologist will conduct an examination of the structures of your eyes: the whites of the eyes, the iris, pupil, eyelids, and eyelashes.
• Your optometrist or ophthalmologist will examine your family medical history, particularly for hereditary diseases such as glaucoma or diabetes.
• Your eyes may be dilated, which allows your eye care specialist to see inside your eye and examine the retina and optic nerve.
• They will test the fluid pressure within your eyes to check for glaucoma.
• In addition to long distance vision, they will also take measurements of metrics that cannot be detected through a screening such as depth perception, color vision, and peripheral vision.

Even if you recently "passed" a vision screening with great results, it does not mean that you can skip out on regular eye exams. The negative effects of many eye diseases can be irreversible, but the earlier a vision problem is diagnosed and treated by a licensed eye care professional, the less likely it is to negatively impact your quality of life.