Final answer:
The order in which eyes are covered when using the Snellen eye chart to test visual acuity is not strictly determined and may vary. Each eye is tested individually, but the initial choice of eye is often at the discretion of the examiner.
Step-by-step explanation:
When using the Snellen eye chart to assess visual acuity, typically either eye can be covered first, and there is no strict rule as to whether the right or left eye should be covered. However, it's common practice in many clinics and optometry offices to start with one eye and then the other, and the sequence can be at the discretion of the professional conducting the test. The most important aspect is that each eye is tested individually to get an accurate measurement of the vision in each eye separately, before testing them together. Common clinical practice may have a preference, but without a specified protocol, the eye to be covered first cannot be determined universally and may vary based on the examiner's routine.
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