What is the purpose of the cover test in a vision examination?

The cover test is specifically designed to evaluate eye alignment and detect the presence of strabismus, which is a condition where the eyes do not properly align with each other when looking at an object. During the test, one eye is covered while the other is focused on a specific target. If the uncovered eye moves to adjust for the covered eye's absence, it indicates that the uncovered eye was not aligned properly, revealing potential issues with the eyes' ability to work together. This test is crucial in diagnosing conditions that can affect both vision and binocular alignment, allowing for early intervention and treatment if necessary.

In contrast, the other options do not align with the primary purpose of the cover test. Assessing color vision involves tests that specifically check color perception rather than alignment. Measuring intraocular pressure typically involves techniques such as tonometry rather than a cover test, and checking for cataracts generally requires an eye examination using slit-lamp biomicroscopy or other methods focused on the lens of the eye, rather than assessing how the eyes align.