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Published on: July 21, 2020
Color vision deficiency in Zahedan, Iran: lower than expected
Hamed Momeni-Moghaddam1, Jason S Ng, Hassan Robabi
1*MSc †OD, PhD ‡BSc Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran (HM-M); Southern California College of Optometry, Marshall B. Ketchum University, Fullerton, California (JSN); and School of Nursing (HR) and School of Rehabilitation (FY), Zahedan University of Medical Sciences, Zahedan, Iran.
Purpose:
To estimate the prevalence of congenital red-green color vision defects in the elementary school students of Zahedan in 2012.
Methods:
In this cross-sectional study, 1000 students with a mean (±SD) age of 9.0 (±1.4) years were selected randomly from a large primary school population. Color vision was evaluated using the Ishihara pseudoisochromatic color plates (38-plate edition). A daylight fluorescent tube was used as an illuminant C equivalent (i.e., 860 lux, color rendering index greater than 92, and color temperature = 6500 K). Having more than three misreadings on the test was considered a failing criterion. Data were analyzed in SPSS version 17 software using χ2 tests.
Results:
Nine students (0.9%) made more than three errors on the Ishihara test. Based on this criterion, the prevalence of red-green color vision deficiency in girls and boys was 0.2 and 1.6% (p = 0.02), respectively.
Conclusions:
The prevalence of red-green color vision deficiency was found to be significantly lower in Zahedan than comparable reports in the literature.
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