Related Experiment Video
Updated: Sep 18, 2025
Author Spotlight: An Automated Method for Assessing Visual Acuity in Infants and Toddlers Using an Eye-Tracking System
Published on: March 17, 2023
Test-retest reliability of swept visual evoked potential measurements of infant visual acuity and contrast
Lotte Lauritzen1, Marianne Hørby Jørgensen, Kim Fleischer Michaelsen
1Center for Advanced Food Studies, Department of Human Nutrition, The Royal Veterinary and Agricultural University, Rolighedsvej 30, 1958 Frederiksberg C, Denmark. ll@kvl.dk
Insights
Swept visual evoked potential (SWEEP-VEP) reliably tracks infant visual development in group means, though individual assessments show variability. The mean threshold best estimates visual acuity with lower test-retest variability.
Area of Science:
- Ophthalmology
- Neuroscience
- Developmental Pediatrics
Background:
- Accurate assessment of infant visual function is crucial for monitoring development and identifying potential issues.
- Swept visual evoked potential (SWEEP-VEP) is a non-invasive electrophysiological method used to evaluate visual pathways.
- Understanding the variability and best estimation methods for SWEEP-VEP data in infants is essential for reliable interpretation.
Purpose of the Study:
- To describe variations in SWEEP-VEP assessment of visual acuity and contrast sensitivity in infants.
- To evaluate the optimal method for estimating visual performance from SWEEP-VEP data in young children.
- To assess the reliability and validity of SWEEP-VEP for tracking visual development in infants.
Main Methods:
- Visual performance was measured in 92 infants (6-40 weeks of age) across two separate visits using SWEEP-VEP.
- Results were validated through repeated tests in seven adults to ensure reliability.
- Statistical analyses included correlation coefficients, coefficients of variation, and comparisons of different threshold estimation methods.
Main Results:
- A strong association was found between repeated infant visual acuity measurements (r = 0.91, p < 0.001) with low inter-assay variation (8.4%).
- The mean threshold, not the maximum, best estimated visual acuity and demonstrated lower test-retest variability (p = 0.001).
- Infant contrast sensitivity showed good test-retest correlation (r = 0.72) but higher inter-assay variation (23%).
Conclusions:
- SWEEP-VEP provides reliable group means for infant visual acuity and contrast sensitivity, effectively describing visual development trends.
- While group data is reliable, the inherent variability of SWEEP-VEP limits its validity for individual infant assessments.
- The mean threshold estimation method is recommended for visual acuity assessment due to its lower test-retest variability.
Abstract:
The aim of the study was to describe variations in swept visual evoked potential (SWEEP-VEP) assessment of visual acuity and contrast sensitivity in infants and to evaluate the best way to estimate visual performance from obtained SWEEP-VEP data. The visual performance of 92 infants (6-40 wk of age) was measured in two separate visits. Results were verified with repeated tests in seven adults. There was a strong association between the two measurements of infant visual acuity (r = 0.91, p < 0.001), with no constant bias and an inter-assay coefficient of variation of 8.4%. The intra-assay coefficient of variation was 17% and in repeated sessions all obtained acuity measures were normally distributed, indicating that the mean and not the maximum threshold best estimates visual acuity. This estimate of visual acuity also had lower test-retest variability than those calculated from the maximum threshold or threshold from the average EEG signals (p = 0.001). Test-retest measures of infant contrast sensitivity had a correlation coefficient of 0.72 (p < 0.001) and an inter-assay coefficient of variation of 23%. With the observed test-retest variability, SWEEP-VEP is less valid for estimating the visual performance of individual subjects, but it can give reliable group means. This method was well suited to describe visual development in the infants, which for acuity as well as contrast sensitivity increased by 0.64 octave per doubling in age. However, the variability of the SWEEP-VEP method can be a limiting factor, for example, in the assessment of the potential effect of dietary docosahexaenoic acid in a homogeneous group of infants.
