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Published on: April 11, 2025
Crowded task performance in visually impaired children: magnifier versus large print.
Bianca Huurneman1, F Nienke Boonstra, Cornelis A Verezen
1Bartiméus, Institute for the Visually Impaired, Zeist, The Netherlands. bhuurneman@bartimeus.nl
Summary
Magnifiers and large print equally improve near vision for visually impaired children. Stronger crowding effects in children with visual impairment lead to greater gains with magnification.
Area of Science:
- Ophthalmology
- Pediatric Vision
- Low Vision Rehabilitation
Background:
- Crowded near vision tasks present challenges for visually impaired children.
- Evaluating assistive devices for near vision is crucial for this population.
Purpose of the Study:
- To compare the effectiveness of a magnifier versus large print for improving crowded near vision task performance in visually impaired children.
- To assess the impact of age and visual acuity on the effectiveness of these low vision aids.
Main Methods:
- Fifty-eight visually impaired children (4-8 years) were divided into magnifier and large print groups.
- Near visual acuity (NVA) and crowded Landolt C acuity were measured with and without magnification.
- Performance metrics included NVA, near vision with magnification, and response time, with working distance monitored.
Main Results:
- No significant performance difference was found between magnifiers and large print for either age group (4-6 and 7-8 years).
- Both magnification types significantly improved NVA in both age groups (p < .001).
- Greater improvements in near vision with magnification were associated with stronger crowding effects (p = .021).
Conclusions:
- A 1.7x magnifier and 1.8x large print are equally effective for improving crowded near vision tasks in visually impaired children.
- Visually impaired children experiencing significant crowding effects benefit more from magnification.
- These findings support the use of both magnifiers and large print as effective low vision aids for young children.
