Childhood vision screening in Canada: public health evidence and practice

Developing a Novel Pediatric Eye Chart Assessing Visual Acuity by Minimum Separable Threshold

The purpose of this study was to develop a new pediatric acuity chart that can assess the minimum separation threshold by incorporating the minimum separation threshold into the picture. To overcome the design limitations of the Landolt ring, two designs of highly versatile minimum separable thresholds that can be easily incorporated into a picture were created: a black, filled circle (the "Circle") and a segment (the "Square"), both with the same break as in the Landolt ring. The three designs-the Landolt ring, Circle, and Square-were used to evaluate and compare the differences in the visual acuity of 21 healthy adults. No significant differences were observed between the results of the visual acuity tested with the Landolt ring, Circle, and Square (Landolt ring vs. Circle: p = 0.92, Landolt ring vs. Square: p = 0.31, Circle vs. Square: p = 0.40). The Bland-Altman analysis revealed no fixed errors between the Landolt ring and Circle and between the Landolt ring and Square (95% CI: -0.09-0.08, -0.09-0.12). Proportional errors were also not observed (p = 0.68, p = 0.41). The Landolt ring, Circle, and Square designs obtained equal results in visual acuity, thus achieving the successful development of a novel pediatric visual acuity chart using these designs.

Utilization and barriers to eye care following school-wide pediatric vision screening

OBJECTIVE

In August 2018, Ontario introduced the Child Visual Health and Vision Screening Protocol outlining school-based senior kindergarten (aged 4-6 years) vision screening. We determine the prevalence of children at risk based on screening in an Ontario community and follow up to determine resource utilization after screening.

METHODS

Vision screening data (HOTV, Randot, Autorefractor) from 41 schools (1127 children) were collected for the 2018-2019 and 2019-2020 school years. Phone follow-up was conducted 1-1.5 years after screening to determine whether an optometry visit occurred, if glasses were prescribed, and potential barriers to accessing eye care. Independent t tests were used to compare time to follow-up between groups, and χ2 testing was used for associations between material and social deprivation.

RESULTS

Overall screening resulted in a 32.2% referral rate within our region. Of the referred children who responded, the rate of seeking out eye care was 69.9% (n = 64), and 65.2% of these visits were prompted specifically by vision screening, and 34.4% of referred children respondents were prescribed glasses. There was a significant relationship between receiving a referral and living in a more materially deprived (p = 0.001) and a more socially deprived area (p = 0.006). The most frequently reported barriers were related to insufficient insurance coverage for eye care or glasses, COVID-19-related difficulties, and scheduling conflicts.

CONCLUSION

Our vision screening program identified and referred more than one third of children screened for follow-up eye examinations, with children in more deprived neighbourhoods being more frequently referred. Around two thirds of referred children sought care, and one third were prescribed glasses in the follow-up sample.

Eye Care in Young Children: A Parents' Perspective of Access and Barriers

Purpose

To evaluate parental perspectives of accessing eye care for children aged under seven years.

Methods

The survey was conducted during September 2020 to March 2021 using online applications and distributed to parents whose children were between the ages of three and seven years. The survey included parents' background, their knowledge of the provision of eye-care services, and the possible barriers that existed to access eye-care services. The relationship between parents' knowledge, barrier scores, level of parental education, and demographic or socioeconomic status was assessed using nonparametric tests.

Results

In total, 1037 questionnaires were completed. The respondents were from 50 cities across Saudi regions. The participants' age was 39 ± 7.5 years, and 54% of them had at least one child under the age of seven (n = 564). Further, 47% had not taken their children for vision screening at reception/year one (n = 467). In addition, 65% of them were not aware of the mandatory screening program at reception/year 1; whereas, only 20% (n = 207) knew how to access eye-care services; and only 39% of the children had undergone any kind of eye or vision test. The pathways to eye care and the cost of eye services/glasses were the main limitations. The parents' responses were significantly influenced by their demographic and socioeconomic characteristics (Kruskal Wallis, P < 0.05).

Conclusion

There was a need for enhancing parent information on how to access eye care for young children and the currently available vision screening programs. Finally, a national protocol to cover the cost of the eye exam as well as spectacle prescription shall be proposed as a mean of incentive.

Amblyopia: A review of unmet needs, current treatment options, and emerging therapies

Amblyopia is a global public health issue with extensive, multifaceted impacts on vision and quality of life (QoL) for both patients and families. Geographical variation exists in the management of amblyopia, with traditional mainstay treatments, optical correction, and fellow eye occlusion most successful when implemented at an early age. In recent years, however, studies demonstrating meaningful improvements in older children and adults have challenged the concept of a complete loss of visual processing plasticity beyond the critical period of visual development, with growing evidence supporting the potential efficacy of emerging, more engaging, binocular therapies in both adults and children. Binocular approaches aim to restore deficits in amblyopia that extend beyond monocular visual acuity impairment, including binocular fusion and visuomotor skills. In view of this, incorporating outcome measures that evaluate the visual performance and functional ability of individuals with amblyopia will provide a clearer understanding of the effect of amblyopia on QoL and a more comprehensive evaluation of amblyopia therapies.

Vision Screening in Children: The New South Wales Statewide Eyesight Preschooler Screening Program

PURPOSE

The aim was to investigate universality of access, screening rate, and outcomes from the New South Wales (NSW) Statewide Eyesight Preschooler Screening (StEPS) over the period of 2009 to 2016.

DESIGN

Cross-sectional, observational study.

METHODS

The StEPS program provides vision screening to 4-year-old children residing in NSW and is administered within Local Health Districts (LHDs). Visual acuity (VA) was examined by trained lay and nurse screeners using HOTV logMAR. Children who had VA <6/9-2 were referred to local practitioners while those with VA <6/18 were referred to public hospital pediatric ophthalmic outpatient clinics where available. Activity data were collected by NSW Health and screening rates determined from population projections of 4-year-olds per LHD based on adjusted 2014 Census data. To determine factors impacting screening and referral rates, a random effects panel analysis was undertaken.

RESULTS

A total of 719,686 (96.4%) NSW 4-year-old children were offered StEPS vision screening between 2009 and 2016, 84% accepted and 564,825 children (75.6%) were screened. The screening rate increased from 67.3% in 2009 to 74.5% in 2016, with an 80% target reached for 3 consecutive years from 2013 to 2015. Of those screened, 19.2% were referred to an eye health professional or advised to have a vision retest in 12 months. This referral rate remained steady over the period studied, with little variation between metropolitan, and rural and regional LHDs.

CONCLUSIONS

StEPS is an ideal service model for preschool vision screening providing coverage that is comparable to school-based screening programs and at an age likely to facilitate optimal treatment outcomes.

National survey of paediatric vision screening programs across Canada: Identifying major gaps and call to action

Objective

Paediatric vision screening programs identify children with ocular abnormalities who would benefit from treatment by an eye care professional. A questionnaire was conducted to assess existence and uptake of school-based vision screening programs across Canada. A supplementary questionnaire was distributed among Ontario’s public health units to determine implementation of government mandated vision screening for senior kindergarten children.

Methods

Chief Medical Officers of Health for each province and territory, and Ontario’s thirty-four public health units were sent a questionnaire to determine: 1) whether school-based vision screening is being implemented; 2) what age groups are screened; 3) personnel used for vision screening; 4) the type of training provided for vision screening personnel; and 5) vision screening tests performed.

Results

Of the thirteen provinces/territories in Canada, six perform some form of school-based vision screening. Two provinces rely solely on non-school-based programs offering eligible children an eye examination by an optometrist and three rely on ocular assessment conducted by a nurse at well-child visits. In Ontario, where since 2018 vision screening for all senior kindergarten students is government mandated, only seventeen public health jurisdictions are implementing universal vision screening programs using a variety of personnel ranging from food safety workers to optometrists.

Conclusion

Good vision is key to physical and emotional development. There is an urgent need for a universal, evidence-based and cost-effective multidisciplinary approach to standardize paediatric vision screening across Canada and break down barriers preventing children from accessing eye care.

Recent Advances in Screening and Treatment for Amblyopia

Amblyopia is the most common cause of monocular visual impairment in children, with a prevalence of 2-3%. Not only is visual acuity reduced in one eye but binocular vision is affected, fellow eye deficits may be present, eye-hand coordination and reading can be affected, and self-perception may be diminished. New technologies for preschool vision screening hold promise for accessible, early, and accurate detection of amblyopia. Together with recent advances in our theoretical understanding of amblyopia and technological advances in amblyopia treatment, we anticipate improved visual outcomes for children affected by this very common eye condition. This article is based on previously conducted studies and does not contain any new studies with human participants or animals performed by any of the authors.

Successes and shortfalls of community Plusoptix photoscreening: results from the iSee study in Southwestern Ontario

OBJECTIVE

The purpose of this work is to provide the final results from a community-wide photoscreening program in Southwestern Ontario for children aged 18 to 72 months, and to estimate the prevalence of amblyogenic risk factors in this population.

STUDY DESIGN

Prospective, multisite photoscreening program.

PARTICIPANTS

5959 children aged 18-72 months were recruited and screened in Southwestern Ontario at 210 locations over a period of 3 years and 4 months.

METHODS

Ophthalmic screening examinations were performed with the Plusoptix S12 photoscreener. The threshold for the referral criteria used was the manufacturer's criteria on receiver operating characteristics 4.

RESULTS

The screening was negative in 5386 children (90.4%), positive in 403 (6.8%), and unreadable in 170 (2.9%); 42% of all screened children were ≤36 months old. The estimated amblyogenic risk factor prevalence of anisometropia was 4.0%, astigmatism was 3.1%, hyperopia was 1.1%, myopia was 0.4%, and strabismus was 0.4%. Of the 403 referred children, 99 (24.5%) completed a formal eye examination based on the responses returned to the study site.

CONCLUSIONS

This is the first Canadian study that provides data on amblyogenic risk factors based on a volunteer-led photoscreening program. Photoscreening is an effective screening tool, particularly for pre-school-aged children; however, the lack of mandatory follow-up to ensure that children receive proper treatment based on cycloplegic refraction reduces the efficacy of screening.

Assessment of availability, awareness and perception of stakeholders regarding preschool vision screening in Kumasi, Ghana: An exploratory study

BACKGROUND

Regardless of the importance of preschool vision screening (PSVS), there is limited data on the current state of these programs in Africa (particularly Ghana). This study sought to investigate the level of awareness and perception of stakeholders regarding PSVS, its availability and related policies/programmes in the Kumasi Metropolis, Ghana.

METHODS

This descriptive cross-sectional study included 100 systematically sampled preschools in the metropolis (using probability proportional-to-size method); 72 private schools and 28 public schools. Convenience sampling was used to recruit stakeholders of preschools (teachers, head teachers, proprietors, administrators, directors, and educationists), and were interviewed using a well-structured questionnaire. Questionnaires were administered to all eligible respondents who were present at the time of data collection.

RESULTS

A total of 344 respondents participated in the study; 123 (35.8%) males and 221 (64.2%) females. The overall mean age of respondents was 37.63 ±12.20 years (18-71 years). Of the respondents, 215 (62.5%), 94 (27.3%), and 35 (10.2%) were enrolled from private schools, public schools, and Metropolitan Education Directorate, respectively. 73.8% of respondents reported the absence of routine PSVS in schools whereas 90.1% reported no written policies for PSVS in schools. Only 63.6% of respondents were aware of PSVS whereas more than half (59.6%) of all respondents perceived PSVS to be very important for preschoolers. Private school ownership was significantly associated with availability of PSVS whereas age, teachers, private school ownership, and preschool experience > 10 years were significantly associated with awareness of PSVS (P < 0.05). However, there was no significant association between sociodemographic factors and perception of PSVS.

CONCLUSION

PSVS is largely unavailable in most Ghanaian schools. Majority of stakeholders were aware of PSVS and agreed to its implementation and incorporation into schools' health programmes. There is the need to implement a national programme/policy on preschool vision screening in Ghana.

Comparison of the pediatric vision screening program in 18 countries across five continents

PURPOSE

Incorporating mass pediatric vision screening programs as part of a national agenda can be challenging. This review assessed the implementation strategy of the existing pediatric vision screening program.

METHODS

A search was performed on PubMed, EBSCO host MEDLINE Complete, and Scopus databases encompassing the past ten years for mass pediatric screening practice patterns that met the selection criteria regarding their objectives and implementation. Results were analyzed from 18 countries across five continents.

RESULTS

Eight countries (44%) offered screening for distance visual acuity only, where the majority of the countries (88%) used either Snellen or Tumbling E chart. High-income countries initiated screening earlier and applied a more comprehensive approach, targeting conditions other than reduced vision only, compared with middle-income countries. Chart-based testing was most commonly performed, with only three countries incorporating an instrument-based approach. Lack of eyecare and healthcare practitioners frequently necessitated the involvement of non-eyecare personnel (94%) as a vision screener including parent, trained staff, and nurse.

CONCLUSIONS

Implementation of a vision screening program was diverse within countries preceded by limited resources issues. Lack of professional eyecare practitioners implied the need to engage a lay screener. The limitation of existing tests to detect a broader range of visual problems at affordable cost advocated the urgent need for the development of an inexpensive and comprehensive screening tool.

Review of school vision screening guidelines

Background: Vision screenings are important in identifying visual anomalies likely to disrupt the physical, intellectual, social and emotional development of children. School health services globally include vision screenings, complementing a variety of associated screening services.Aim: This review article provides evidence for content, provision and efficacy of the vision screening services for children of school-going age and reports on the current practice of children’s vision screenings worldwide including in South Africa.Methods: Studies were identified from PubMed, Ebscohost and Science Direct with the search terms utilised during the selection of electronic articles and journals for the review. The target population includes children of school-going age from 6 to 19 years without previously known conditions associated with visual anomalies and learning-related problems. The quality of vision screening programmes and policies for the school-going age children in different countries were evaluated using Wilson and Jungner criteria.1Results: Vision screening programmes worldwide appear to support comprehensive vision screening methods among pre-schoolers (from birth to ≤ 6 years vs. children of school-going age). The development of vision screening procedures in some countries in the United States of America (USA) was found to be grounded on epidemiologic findings and principles. These may have contributed towards the formulation of national vision screening guidelines for pre-schoolers that supported the detection of amblyopia and its associated conditions such as strabismus, anisometropia and myopia. School-going children’s vision screenings are not supported worldwide as research has shown that there is lack of benefits for detecting other visual anomalies such as vergence and accommodative dysfunctions. This is despite evidence provided by the literature reviewed that an association exists between prevalent accommodation and vergence dysfunctions including poor ocular motilities and poor near-vision, among children of school-going age with poor academic performance.Conclusion: The guidelines worldwide support school vision screenings, especially for the pre-schoolers by the school health nurses, with other programs having considered the teachers, optometrists or orthoptists as the appropriate personnel to conduct the school vision screenings. There is still a need for the effectiveness of the school vision-screening programmes to be investigated related to the importance of detecting convergence and accommodative dysfunctions for the school going age children.

Paediatric vision screening in the primary care setting in Ontario

Objectives

Early intervention is critical to prevent treatable causes of vision loss in children. The objectives of the current study are: (1) to assess how well primary care physicians in Ontario follow the vision screening guidelines for children as recommended by the Canadian Paediatric Society and the Rourke Baby Record and (2) to identify barriers to vision screening in the primary care setting.

Design

Cross-sectional survey.

Methods

A 19-question survey was mailed out to 1000 randomly selected family physicians (family MDs), 1000 general practitioners (GPs) and 1000 paediatricians in Ontario as listed in the 2013 Canadian Medical Directory.

Results

A total of 719 completed surveys were included in the analysis (449 from family MDs/GPs and 270 from paediatricians). Vision screening was reported to be performed by 65% of family MDs/GPs and 52% of general paediatricians at every well child visit. While red reflex was reported to be checked by 94% of all physicians in children under 3, it was only performed by 25% of respondents for children over 3. Thirty seven percent of all physicians reported never performing a visual acuity test in any age group. When asked about the obstacles preventing them from performing vision screening, lack of training (family MDs/GPs: 50%, paediatricians: 42%), time constraints (family MDs/GPs: 42%; paediatricians: 40%) and inadequate reimbursement (family MDs/GPs: 17%; paediatricians: 15%) were the most commonly cited reasons.

Conclusions

Strategies to improve vision screening are necessary given that early intervention is crucial to prevent treatable causes of vision loss in children.

Weighing in on Canadian school-based vision screening: A call for action

Vision-screening programs are designed to detect common causes of visual impairment and increase the likelihood of early diagnosis and treatment. In the health authority Eastern Health - Newfoundland and Labrador, public health leaders raised a concern about the efficiency and effectiveness of the current non-routine, opportunistic vision screening protocol for school-aged children. An environmental scan of screening practices and programs across Canada was conducted, yielding a wide range of inconsistencies with respect to program type, target population, and screening tools. A significant gap in evidence-based research into universal vision-screening programs for the school-aged population (6+) was also noted. In light of these findings (both in practice and research), we recommend that researchers and public health practitioners across the country evaluate their current practice with respect to school-based vision screening and disseminate their findings through publication. We conclude that evaluation and research into current school-based screening programs (both opportunistic and universal) will provide the evidence needed to guide practice.

Amblyopia screening in Bulgaria

PURPOSE

To determine the prevalence of amblyopia and the average age at first ophthalmological examination of school-aged children from northwestern Bulgaria.

METHODS

Visual acuity testing, stereopsis, orthoptics, ocular motility, non-cycloplegic refraction, direct ophthalmoscopy, and external ocular inspection were performed. Cycloplegic refraction and indirect ophthalmoscopy were done as necessary. A total of 2,054 children (1,020 girls and 1,034 boys) were divided into three age groups: 6 to 8 years (803 children), 8 to 10 years (719 children), and 10 to 12 years (530 children).

RESULTS

A total of 1,861 children (90.6%) received their first examination: 754 (93.9%) aged 6 to 8 years, 638 (88.7%) aged 8 to 10 years, and 469 (88.2%) aged 10 to 12 years. Amblyopia was detected in 88 children (4.3%): 42 (5.2%) aged 6 to 8 years, 27 (3.8%) aged 8 to 10 years, and 19 (3.6%) aged 10 to 12 years. The first group had higher prevalence compared to countries with well-developed screening programs. Refractive errors were detected in 403 children (19.7%): 125 (15.6%) aged 6 to 8 years, 146 (20.3%) aged 8 to 10 years, and 132 (24.8%) aged 10 to 12 years. The estimated prevalence increases with age. Strabismus was detected in 24 children (1.2%): 8 (1.0%) aged 6 to 8 years, 7 (1.0%) aged 8 to 10 years, and 9 (1.7%) aged 10 to 12 years.

CONCLUSIONS

The lack of screening programs in Bulgaria is the main reason for late diagnosis of amblyopia. The "Do Good "project provided eye examination of school-aged children aged 6 to 12 years, when amblyopia is curable. This model could be used in establishing a Bulgarian national screening program.

Vision screening in preschoolers: the New South Wales Statewide Eyesight Preschooler Screening program

OBJECTIVE

To evaluate screening and diagnostic outcomes of the New South Wales Statewide Eyesight Preschooler Screening (StEPS) program, a state-funded, universal vision screening program for 4-year-old children.

DESIGN, SETTING AND PARTICIPANTS

A cross-sectional evaluation of the StEPS program, in which eligible 4-year-old children were offered a vision screen in local health districts in NSW, between 1 July 2010 and 30 June 2011.

MAIN OUTCOME MEASURES

Number and proportion of eligible children who were offered screening; accepted screening; were screened and scored a pass or were referred (routinely or urgently) for further vision assessment; and were referred for further assessment and required intervention.

RESULTS

Of 91 324 eligible 4-year-olds in NSW, 80 328 (88.0%) were offered screening, and 65 834 (72.1% of the eligible population) were screened. Of the children who were screened, 3867 (5.9%) scored less than 6/9-2 but better than 6/18 in one or both eyes and were referred to their general practitioner or eye health professional for further vision assessment. A further 1425 children (2.2%) scored 6/18 or less in one or both eyes and were referred for high-priority assessment. In the two local health districts with the most complete follow-up data, 704 of 779 children (90.4%) with routine referrals and 278 of 285 (97.5%) with high-priority referrals required treatment or review at a later date.

CONCLUSIONS

The StEPS program has achieved a high screening participation rate in NSW. Many children have been diagnosed and received treatment for previously undetected serious vision disorders that may otherwise have been diagnosed too late for effective intervention.