What are the current research gaps in visual screening using Visual Acuity (VA) versus instrument-based screening in detecting vision problems in children?

From the Guidelines

Current research gaps in visual screening for children include the need for more direct comparisons between traditional visual acuity testing and instrument-based screening methods, with a focus on determining optimal screening frequencies, age-specific protocols, and cost-effectiveness in various settings and populations. While visual acuity testing using eye charts (like HOTV or LEA symbols) remains the standard approach, instrument-based screening using photoscreeners and autorefractors is gaining popularity, as noted in the 2023 study by Hutchinson et al. 1. However, we lack sufficient long-term outcome data comparing these methods, particularly regarding their effectiveness in different age groups. Research is needed to determine optimal screening frequencies and age-specific protocols, as current guidelines vary, and more studies are needed on the impact of early detection through different screening methods on educational outcomes and quality of life, as highlighted in the 2023 study published in Ophthalmology 1.

Some of the key areas that require further research include:

• Determining the optimal age for initiating instrument-based screening, with some studies suggesting that photoscreening can be effective in children as young as 12 months 1
• Comparing the effectiveness of different instrument-based screening methods, such as photoscreening and autorefraction, in detecting amblyopia risk factors and other vision problems 1
• Evaluating the cost-effectiveness of instrument-based screening in various settings and populations, including resource-limited settings, as noted in the 2016 American Academy of Pediatrics (AAP) update on routine preventive pediatric health care 1
• Developing standardized training requirements for personnel conducting different types of vision screening in children, to ensure that screenings are accurate and reliable, as emphasized in the 2023 study published in Ophthalmology 1

Ultimately, addressing these research gaps will help establish evidence-based, standardized approaches to pediatric vision screening across different healthcare systems, and improve outcomes for children with vision problems, as highlighted in the 2023 study by Hutchinson et al. 1.

From the Research

Current Research Gaps in Visual Screening

The current research gaps in visual screening using Visual Acuity (VA) versus instrument-based screening in detecting vision problems in children are:

• Limited direct evidence on the effectiveness of preschool vision screening for improving visual acuity or other clinical outcomes 2
• Need for additional studies to better understand the effects of screening compared with no screening 2
• Uncertain evidence on whether vision screening in children under three years of age provides net benefits 3
• Limited research on the effectiveness of instrument-based screening in pediatric primary care settings, despite recent recommendations from professional groups 4
• Need for further research on how to overcome barriers to the widespread use of instrument-based vision screening technology in pediatric primary care settings 4

Comparison of VA and Instrument-Based Screening

Both VA and instrument-based screening have their own strengths and limitations:

• VA screening is widely used and has been shown to be effective in detecting amblyopia and its risk factors 5, 3
• Instrument-based screening has been shown to be effective in detecting vision problems in preschool-aged children and may result in a reduction in unnecessary referrals to eye care specialists 4
• However, there is limited research on the comparative effectiveness of VA and instrument-based screening in detecting vision problems in children 6, 5, 4

Future Research Directions

Future research should focus on:

• Conducting randomized trials and controlled observational studies to evaluate the effectiveness of VA and instrument-based screening in detecting vision problems in children 2
• Investigating the cost-effectiveness and feasibility of implementing instrument-based vision screening in pediatric primary care settings 4
• Developing and evaluating new screening tests and technologies that can improve the accuracy and efficiency of vision screening in children 6, 5