What test is commonly used to help determine color deficiencies?

The Ishihara test is specifically designed to identify color deficiencies, particularly red-green color blindness. It consists of a series of plates, each featuring a pattern of colored dots that forms numbers or shapes. The ability to accurately perceive these numbers or shapes depends on the viewer's color discrimination abilities, making it an effective tool for assessing color vision deficiencies. The test is straightforward and requires no special equipment beyond the plates themselves, which are widely available and easy to use in various settings.

In contrast, other tests listed are used for different purposes. The Snellen test evaluates visual acuity and is primarily used to measure the sharpness of vision. The cover test examines eye alignment and binocular vision by observing how the eyes respond when one is covered, and the visual field test assesses the completeness of a patient's peripheral vision. These tests do not provide information about color perception and thus are not suitable for diagnosing color deficiencies.