Simple vision screenings give limited insight into the health of your eyes, much like getting your blood pressure checked but not getting the rest of your annual physical. On the other hand, a comprehensive eye exam provides a complete perspective into your overall eye health by factoring in much more information about your eyes and general health.
Comprehensive eye exams evaluate all aspects of your vision and eye health, examining your eyes internally and externally for any signs of eye disease. These tests include:
External exams, which evaluate the whites of your eyes, irises, pupils, eyelids, and eyelashes
Internal exams, which evaluate your retinas and optic nerves while your eyes are dilated
Visual function and eye health tests, which evaluate your depth perception, color vision, peripheral vision, and response of your pupils to light
Glaucoma testing, which evaluates the fluid pressure within your eyes
Visual acuity, which evaluates if glasses or contact lenses can improve your vision
Comprehensive eye exams treat eyes holistically, factoring in your overall health history including your blood pressure, the amount of sun exposure you get, and whether or not you have diabetes, smoke, or take medications.
They only test visual acuity, or your ability to see clearly in the distance, and do not provide insight into the health of your eyes.
They are typically conducted by individuals who have not been trained in eye health at your annual physical, school, work, or other places lacking extensive testing equipment.
The test is frequently limited to an eye chart across the room, which fails both to test various distances and to take into account factors like room lighting, which can affect test results.
The American Optometric Association (AOA) recommends that adults between the ages of 18 and 64 get an in-person eye exam every year regardless of their eye health.