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Childhood vision screening in Canada: public health evidence and practice
Silvina C Mema1, Lynn McIntyre, Richard Musto
1Department of Community Health Sciences, Faculty of Medicine, University of Calgary, Calgary, AB. scmema@ucalgary.ca
Insights
Public health should screen for amblyopia (lazy eye) in preschoolers to prevent vision loss. Canada has inconsistent screening programs, creating disparities in care and increasing the risk of preventable blindness.
Area of Science:
- Public Health
- Ophthalmology
- Pediatrics
Background:
- Best practice guidelines advocate for preschool vision testing to prevent amblyopia.
- Universal vision screening in children aged 3-5 remains a controversial public health issue.
- Amblyopia screening responsibilities in Canada are shared among physicians, optometrists, and Public Health.
Purpose of the Study:
- To review evidence for preschool vision screening for amblyopia using an Evidence-based Public Health (EBPH) approach.
- To assess the implications for Public Health provision of universal screening programs in Canada.
- To consider current screening practices across Canadian jurisdictions.
Main Methods:
- Literature search addressing key screening criteria (disease, test, treatment, program requirements).
- Reappraisal of studies from existing systematic reviews on vision screening impact.
- Survey of Chief Medical Officers of Health regarding existing Public Health preschool vision screening programs.
Main Results:
- Evidence supports Public Health-led amblyopia screening based on EBPH criteria and intervention studies.
- A significant disparity exists in Canadian amblyopia screening practices.
- Some provinces have organized programs, while others delegate screening without monitoring uptake disparities.
Conclusions:
- Public Health attention is crucial for amblyopia prevention.
- Existing screening programs should be maintained.
- Provinces lacking organized programs should reassess their role in preventing inequities and avoidable blindness.
Objectives:
Best practice guidelines recommend vision testing in children 3 to 5 years of age for the prevention of amblyopia; however, universal vision screening is controversial. In Canada, amblyopia screening can be the responsibility of physicians, optometrists, and/or Public Health. We review the evidence underlying preschool vision screening for amblyopia using an Evidence-based Public Health (EBPH) approach, and consider implications for the Public Health provision of universal screening programs for amblyopia in Canadian jurisdictions in light of present practices.
Methods:
We searched the literature to address each major screening criterion (disease, test, treatment, program requirements) necessary to support preschool vision screening for amblyopia. We also reappraised papers cited in two systematic reviews related to the impact of vision screening. The Chief Medical Officer of Health of each province/territory was sent a short survey asking whether there currently was a Public Health preschool vision screening program in place and if so, for specifics about the program.
Results:
An EBPH approach to the literature with respect to the criteria for screening and available intervention studies support amblyopia screening by Public Health. There is a public health divide in amblyopia screening practice in Canada; while some provinces maintain organized programs, others have chosen to delegate the task to other professionals, without a concurrent surveillance function to monitor disparities in uptake.
Conclusions:
Amblyopia deserves attention from Public Health. Efforts should be made to maintain existing programs, and provinces without organized screening programs should reconsider their role in the prevention of inequities with regard to preventable blindness in Canadian children.
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