White male children have the highest prevalence—one in 20—of color blindness among four major ethnicities, according to a study of more than 4,000 preschoolers, published online in Ophthalmology. Color blindness is least common in African-American boys.
Girls of any ethnicity have almost no color blindness—0% to 0.5%—which confirms prior research.
In the study, researchers from the Multi-Ethnic Pediatric Eye Disease Study Group tested 4,005 California preschool children ages 3 to 6. They found the following prevalence for boys of different ethnicities:
• 5.6% of white boys
• 3.1% of Asian boys
• 2.6% of Hispanic boys
• 1.4% of African-American boys
While the researchers found that children at the youngest ages could not accurately complete testing, they say the findings suggest that successful color vision screening can begin at age 4.
Children with color blindness often perform poorly on tests or assignments that use color-coded materials, leading color blind children to be inappropriately classified by ability at school, says the study’s principal investigator Rohit Varma, MD, chairman of the Department of Ophthalmology at the University of Southern California Keck School of Medicine.
“It’s not that the child is not smart enough or bright enough,” Dr. Varma says. “It’s that they see the world a little differently.”
Children with color blindness can benefit from different kinds of learning materials to demonstrate their understanding of concepts, despite their inability to see colors correctly, Dr. Varma says. “That needs to start early on because labeling a child as not smart or bright enough is a huge stigma for the child and causes significant anxiety for the parents and family,” he says.
Xie JZ, Tarczy-Hornoch K, Lin J, et al; Multi-Ethnic Pediatric Eye Disease Study Group. Color vision deficiency in preschool children: The Multi-Ethnic Pediatric Eye Disease Study. Ophthalmology. Article in press. [Epub ahead of print]