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Prevalence of Color Vision Deficiency in an Adult Population in South Korea.

SIGNIFICANCE
Large differences in failure rates for color vision screening have been reported among different regional groups. However, color vision deficiency prevalence in Korea has only been investigated within a small area of the country.


PURPOSE
This study examines the prevalence of failing a color vision screening and its sex-related differences using a sample that is representative of the whole Korean population.


METHODS
This population-based cross-sectional study evaluated 2686 subjects (age, 19 to 49 years) who participated in the sixth Korea National Health and Nutrition Examination Survey (2013). Color vision deficiency was assessed using the Hardy-Rand-Rittler (HRR) test by an ophthalmologist. According to standard criteria for the HRR, it classified each subject as color normal, protan, deutan, tritan, or unclassified color vision loss. All participants had comprehensive medical evaluations and ocular history taken.


RESULTS
The weighted overall prevalence of color vision deficiency in the Korean population was 3.9% (95% confidence interval, 3.0 to 5.4%). The prevalence of color vision deficiency was higher in male participants (6.5%) than in female participants (1.1%). Among all participants, deutan deficiency (2.5%) had a higher prevalence than did protan deficiency (0.4%). For male participants who failed the HRR screening, deutan-type deficiency was detected most often (64.2%), whereas an unclassified color vision deficiency type was the most common (52.9%) among female participants who failed the HRR screening. As expected, male participants were more likely to fail the HRR screening compared with female participants (prevalence ratio, 6.08; 95% confidence interval, 3.61 to 10.26).


CONCLUSIONS
This large population-based study of color vision deficiency among Koreans gives the most accurate estimate of failing a color vision screening test to date and provides useful information for planning adaptive strategies.