During visual acuity testing using the Snellen chart, children should be instructed to do which of the following?

Instructing children to keep both eyes open during the visual acuity test using the Snellen chart is essential for accurately assessing their vision. When both eyes are open, it allows for natural binocular vision, which can improve the ability to gauge clarity and perception of depth. This approach is particularly important for children, as they may be more prone to discrepancies in vision between their two eyes.

Maintaining both eyes open also helps prevent potential misinterpretation of visual acuity results that might occur if one eye is closed, as this can lead to an inaccurate representation of their overall vision performance. Additionally, closing one eye could limit the child's ability to use their full visual capacity, which is crucial for comprehensive vision assessment.

The recommended distance for testing is typically 20 feet, which may vary slightly based on specific testing protocols, but standing 5 feet away is not standard for the Snellen chart, which does not account for standard visual acuity testing distances. It's also not appropriate for children to remove their glasses during the exam unless specified by an eye care professional, as this may compromise an accurate assessment of their visual acuity while wearing corrective lenses.