Frequency of Color Blindness Among Secondary School Students in Al-Diwaniya City, Iraq

Background: Color blindness (also known as color vision deficiency, or CVD) is an inherited or acquired condition that interferes with the ability to discriminate certain wavelengths of the visible light spectrum. CVD has a well-documented prevalence among the Middle Eastern population and has been shown to have negative effects on academic achievement. No systematic epidemiological studies have been carried out in Al-Diwaniya City, Iraq concerning the prevalence and type distribution of CVD in secondary school students. Objective: This cross-sectional study aims to assess the prevalence and type distribution of CVD in secondary school students in Al-Diwaniya City, Iraq, and to evaluate the level of prior awareness and diagnosis among individuals diagnosed with CVD. Methods: A sample of 1500 secondary school students (762 males, 738 females) aged 12-18 years old was randomly selected from 20 secondary schools in Al-Diwaniya City and surveyed during the 2023-2024 academic school year. A color vision examination was administered using Ishihara pseudoisochromatic plates (38-plate edition) as the primary screening tool and the Farnsworth-Munsell 100 Hue test as the confirmatory classification tool for the screen positive cases. Demographic information was obtained, including prior awareness and formal diagnosis, as well as academic difficulties experienced due to CVD using a structured questionnaire. Results: CVD was identified in 69 students, which resulted in an overall prevalence of 4.6% (95% CI: 3.58-5.82). The prevalence of CVD was statistically higher in males (7.48%) compared to females (1.63%; p<0.001). Of the 69 students diagnosed with CVD, 89.9% of the cases were red-green deficiencies and the most common type of CVD was deuteranomaly. Only 13.0% of the secondary school students diagnosed with CVD had received a formal diagnosis before the current study, while 59.4% have reported experiencing academic difficulties due to CVD. Conclusion: CVD is prevalent among secondary school students attending school in Al-Diwaniya City; however, most students diagnosed with CVD have not received prior formal diagnoses. Therefore, routine color vision screening should be added to the school enrollment process in addition to modifications to color-coded educational materials.