Comprehensive Eye Exams

Eye Care Benefits Toolkit

Eye Health Basics: Comprehensive Eye Exams

Comprehensive Eye Exams

What is the difference between a comprehensive eye exam and a simple screening?

Comprehensive eye exams, performed by a doctor of optometry, are considered the gold standard in clinical vision care. They are more precise, thorough and broad-scoped than screenings and play a vital role in detecting vision issues and common eye conditions. These exams are also important in the early detection and ongoing management of some costly chronic conditions such as diabetes, hypertension and cancer.

In addition to the patient’s history, the doctor of optometry’s assessment of eye and vision health will likely  include:

  • Eye Structure Examination: Assessment of all structures of the eye, internally and externally, that may affect vision; evaluation of general health, diseases (including neurological issues and systemic conditions) and vision conditions
  • Preliminary Tests: Evaluates depth perception, color vision, eye muscle movements, peripheral or side vision and the way pupils respond to light
  • Visual Acuity Measurement: Evaluates the vision clarity of each eye (using the “eye test”) including reading letters or symbols on charts at near and far distances
  • Refraction: Determines the lens power needed to compensate for any refractive error, such as nearsightedness, farsightedness or astigmatism. This test determines the prescription strength for corrective lenses
  • Keratometry: Measures the curvature of the cornea (clear outer surface of the eye) by focusing a circle of light on the cornea and measuring its reflection; this test is critical in determining the proper fit for contact lenses
  • Eye Focusing, Eye Teaming and Eye Movement Testing: An assessment to determine how well the eyes focus, move and work together, which is critical for children learning how to read
  • Eye Health Evaluation/Internal and External Examination of the Eye/Supplemental Testing: Additional tests that may be required to rule out possible problems, clarify uncertain findings or provide a more in-depth assessment
  • Glaucoma Test (age based): Used to determine if increased pressure within the eyeball is occurring, causing gradual loss of sight

A comprehensive eye exam is one of the most important preventive ways to preserve vision, and the only way to accurately assess eye health, diagnose an eye disorder or disease, and determine the need for corrective lenses.


Vision screening is a short test that allows for the possible identification, but not diagnosis, of some eye disorders and conditions. This type of screening may be performed by a variety of health care professionals. Visual acuity screening tests are often given in a doctor’s office as part of a physical exam or at a driver’s license facility. One type of vision screening may identify possible amblyopia (or lazy eye) in children, while another type focuses on potential glaucoma in adults. No combination of screenings can match the testing and diagnoses in a comprehensive eye exam.  Only the eye exam can enable an eye doctor to diagnose the cause of symptoms identified by screening, and initiate treatment, if necessary.

Unfortunately, some patients might be confused by companies that claim to be able to provide a vision screening or test online. Some may claim that using an online vision screening app is less expensive, but in reality, undiagnosed vision and overall health issues can cause greater long-term economic and physical costs. According to the 2018 American Eye-Q® Survey, 87% of people surveyed don’t think an online vision screening app is a substitution for a comprehensive eye exam.