City Research Online

Abstract

Objective
Scotland’s comprehensive orthoptist-led vision screening program for children (3.5-5.5 years) has participation of ∼85% (∼45,000 annually). Tests include presenting vision, cover test, and other orthoptic evaluations. Screening failures are referred for an eye examination, including cycloplegic refraction, by an optometrist/ophthalmologist. Primary objectives: report prevalence of amblyopia risk factors (ARFs) in a defined population. Secondary objective: investigate associations between ARFs and deprivation/housing/location.

Design
Retrospective cohort and trend study.

Participants
Scottish children aged 3.5 to 5.5 years.

Methods
ARFs considered were constant manifest strabismus, hyperopia (spherical equivalent refraction, SER) >+4.00D (one/both eyes), astigmatism >1.75DC (one/both eyes), anisometropia >1.25DC for astigmatism and >1.25D (SER) for hyperopic or mixed anisometropia. Data are from 2013/14, 2014/15, 2015/16, 2020/21, and 2021/22 school years, from Health Boards containing 87% of Scotland’s population.

Main outcome measures
Refractive error and cover test results.

Results
Prevalence (95% CI) of ≥ one ARF ranged from 4.41% (4.21-4.60, 2013-14) to 5.15% (4.92-5.38, 2021-22), with no statistically significant relationship between prevalence of any ARF and time (for Bonferroni corrected adjusted P-value = .008). In 2021 to 22, for children with ≥1 ARF, 48.23% had astigmatism, 35.10% hyperopia (SER), 26.59% hyperopic anisometropia (SER), 13.73% constant manifest strabismus and 12.64% astigmatic anisometropia. Correlations between ARFs and deprivation/housing/location were not significant (P = .06 to 1.00). For all years, odds ratios for referral following screening failure in quintile 1 (most deprived) were significantly higher (39% to 60% higher, P < .001) than middle quintile 3.

Conclusions
In this Scottish population (3.5 to 5.5 years) the prevalence of children with ≥1 ARF was approximately 5%, validating the universal vision screening program’s importance. Children in the most deprived quintile were significantly more likely to fail screening.

Publication Type:	Article
Additional Information:	© 2026 Published by Elsevier Inc. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/
Publisher Keywords:	vision screening, school screening, amblyopia risk factors, amblyopia, Scotland, deprivation
Subjects:	R Medicine > RE Ophthalmology R Medicine > RJ Pediatrics > RJ101 Child Health. Child health services
Departments:	School of Health & Medical Sciences School of Health & Medical Sciences > Department of Optometry & Visual Science
SWORD Depositor:	Symplectic Administrator

Export

Downloads