From the Guidelines
Instrument-based vision screening is more effective than visual acuity (VA) testing in children younger than 5 years old, as it can objectively assess refractive errors, media opacities, and eye alignment without requiring the child's verbal response or sustained attention 1. Traditional VA screening methods like eye charts require a child to identify letters or symbols and verbally communicate their responses, which depends on cognitive development, language skills, and cooperation that many preschool children haven't yet mastered.
Key Points
- Instrument-based screening tools such as photoscreeners and autorefractors can quickly capture measurements (often in less than a second) and can be used successfully in children as young as 6 months of age 1.
- The American Academy of Pediatrics and American Academy of Ophthalmology support instrument-based screening for children ages 1-5 years, transitioning to VA testing when children become more cooperative and verbally proficient, typically around age 5 1.
- Instrument-based screening helps identify vision problems like amblyopia, strabismus, and significant refractive errors during the critical period of visual development when treatment is most effective, potentially preventing permanent vision loss 1.
- The sensitivity and specificity of instrument-based screening devices depend on the referral criteria used, and guidelines for a uniform set of amblyopia risk factors that should be detected by instrument-based screening are available 1.
Recommendations
- Instrument-based vision screening should be used in children under 5 years old, especially in those who are preverbal, preliterate, or developmentally delayed 1.
- Primary care providers should perform vision screening of newborns and infants under 6 months of age, including red reflex testing and external inspection of ocular and periocular structures 1.
- Children who fail to complete subjective visual acuity assessment or have abnormal findings on vision screening should be referred for a comprehensive eye examination 1.
From the Research
Effectiveness of Instrument-Based Screening
- Instrument-based screening is considered an alternative to vision charts for testing visual acuity in children aged 3-5 years, as recommended by the American Academy of Pediatrics 2.
- This method can be more effective in young children due to the literacy requirements of traditional Visual Acuity (VA) screening, which may not be suitable for children under the age of 5.
- Studies have shown that instrument-based screening can increase completed screening rates among preschool-aged children, with improvements ranging from 54% to 89% 3 and 65.3% to 86.5% 4.
Comparison with Visual Acuity Screening
- Visual Acuity (VA) screening using optotype-based tests may not be as effective in young children due to literacy requirements, whereas instrument-based screening can detect amblyogenic risk factors such as refractive error, media opacities, and eye misalignment 5.
- Instrument-based screening has been associated with a 15% reduction in referrals to eye care specialists, suggesting that it may be a more accurate and efficient method for detecting vision problems in young children 3.
Implementation in Primary Care Settings
- Instrument-based vision screening can be effectively implemented in primary care settings, with significant improvements in completed screening rates among 3- to 5-year-old children 3, 4.
- The use of portable vision screening devices has been shown to increase completed screening rates, with improvements greatest among 3-year-olds 4.