Identification of colorblindness among selected primary school children in Hararghe Region, Eastern Ethiopia

Abstract

Background: Color vision deficiency or colorblindness, is the inability or reduced ability to distinguish different color spectra, particularly, red & green under normal lighting conditions with unaided eye. Redgreen colorblindness is heritable genetic disorder and most prevalent type of color vision deficiency and its incidence varies between different ethnicity and sex and shows disparity in different parts/regions of the world.

Objectives: This study was conducted to find out the prevalence of colorblindness in Eastern part of Ethiopia and identify its distribution among Harari, Oromo and Ethio-Somali ethnic groups.

Methods: A total of 2103 (1043 male & 1060 female) students belonging to the three ethnic groups were randomly selected from nine selected primary schools and were screened for color vision deficiency by using Ishihara’s tests for color vision deficiency and the data analysis was carried out with SPSS version 16.0.

Results: Among those screened for color vision deficiency, 33 of them (1.6%) were diagnosed with colorblindness out of which 31 were male and 2 were female. Out of this; 15, 7 and 11 were from Harari, Oromo and Somali ethnicity respectively. The highest incidence was observed among Harari males (4.2%) and no color vision deficiency was recorded among Oromo females. Deuteronomally was the most frequent color vision defect detected (16, 48.5%) and protanopia was the least detected color vision deficiency with 4 cases (12.1%).

Conclusion: Results from this study show similar prevalence rate with previously reported study in Ethiopia for Harari ethnic group but lower prevalence rates for Somali and Oromo ethnic groups. Early detection of colorblindness is important for children to select their future profession and take necessary precautions in their everyday activities. Families and other concerned bodies should also take the case of children with colorblindness into consideration while dealing with them.

Keywords: Color vision deficiency, Red-green, Ishihara test, Eastern Ethiopia