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Is screening for congenital colour vision deficiency in school students worthwhile? A review
Nishanthan Ramachandran1, Graham A Wilson, Nick Wilson
1University of Otago, Wellington, New Zealand. ramni260@student.otago.ac.nz.
Insights
Routine screening for congenital colour vision deficiency in schools is not recommended. Evidence does not support its link to road safety, education, or significant health impacts, questioning the value of widespread testing.
Area of Science:
- Ophthalmology
- Public Health
- Optometry
Background:
- Congenital colour vision deficiency (CCVD) screening in schools often uses the Ishihara test.
- Screening programs are evaluated against Wilson and Jungner criteria.
Purpose of the Study:
- To review the literature on screening for CCVD in school students.
- To assess the validity and utility of CCVD screening programs based on established criteria.
Main Methods:
- Literature review analyzing studies on CCVD screening in school populations.
- Evaluation of screening test performance (Ishihara test) and condition impact (road safety, occupation, education).
Main Results:
- CCVD is not definitively linked to increased road traffic crashes or educational attainment.
- The Ishihara test demonstrates good performance for red-green deficiencies.
- Occupational restrictions and the value of school screening for these are questionable.
- Limited interventions exist, mainly management-focused (e.g., tinted lenses).
Conclusions:
- Routine CCVD screening in schools is not supported by current evidence.
- Referral for screening may be beneficial for students pursuing specific occupations with colour vision requirements.
- Discontinuing or not adopting school-based CCVD screening programs is advisable.
Abstract:
This review analyses the literature on screening for congenital colour vision deficiency in school students, which predominantly uses the Ishihara test. The review was framed with respect to the established Wilson and Jungner criteria for screening programs. These criteria relate to the characteristics of the condition concerned, the performance of the screening test, the existence of treatment options and the performance of screening programs. The literature reviewed suggests that congenital colour vision deficiency has not been shown to increase risk of road traffic crashes and is not a preclusion to driver licensing in most developed countries. The occurrence of congenital colour vision deficiency has been used to limit entry into certain occupations; however, the value of screening school students with regard to occupational preclusion is questionable. Stronger evidence exists indicating no association between congenital colour vision deficiency and level of educational achievement. Studies showing any association between congenital colour vision deficiency and other health and lifestyle impacts were rare. The most commonly used screening test (using Ishihara pseudoisochromatic plates) performs well with respect to detecting red-green colour vision deficiencies. Finally, the only interventions we identified for congenital colour vision deficiency were management ones around the availability of specific tinted lenses and computer programs to aid colour perception in certain tasks. Given this picture, the weight of evidence appears to be in favour of not adopting (or discontinuing) routine colour vision screening programs for school students; however, it may be worthwhile for a career advisor to refer school students to an optometrist or ophthalmologist for colour vision screening, upon expression of interest in an occupation where normal colour vision is either particularly desirable or is a regulatory requirement.
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