African-Americans have lowest rate of color blindness among young males
SAN FRANCISCO — The first major study of color blindness in a multi-ethnic group of preschoolers has uncovered that Caucasian male children have the highest prevalence among four major ethnicities, with 1 in 20 testing color blind. Researchers also found that color blindness, or color vision deficiency, in boys is lowest in African-Americans, and confirmed that girls have a much lower prevalence of color blindness than boys. The study is being published online today in Ophthalmology, the journal of the American Academy of Ophthalmology.
Despite the name, color blindness is not a type of blindness, but an inability to see colors accurately. The most common form of color blindness is genetic and involves a mutation or lack of genes that help the eye see red or green. People with this form of color blindness cannot tell the difference between the two colors. As this can negatively impact performance in school, early diagnosis of color deficiency is important so that parents and teachers of color blind children are aware and able to provide adaptive learning tools and strategies for these children.
Researchers from the Multi-Ethnic Pediatric Eye Disease Study Group tested 4,005 California preschool children age 3 to 6 in Los Angeles and Riverside counties for color blindness. They found the following prevalence by ethnicity for boys:
- 5.6 percent of Caucasian boys
- 3.1 percent of Asian boys
- 2.6 percent for Hispanic boys
- 1.4 percent of African-American boys
The prevalence of color blindness in girls measured 0 percent to 0.5 percent for all ethnicities, confirming findings in prior studies. However, the numbers were so low overall for girls that researchers say they cannot statistically compare rates between females among the four ethnicities studied.
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. Many times children with color blindness will perform poorly on tests or assignments that employ color coded materials, leading color blind children to be inappropriately classified by ability at school, said the study's principal investigator Rohit Varma, M.D., chairman of the Department of Ophthalmology at the University of Southern California (USC) Keck School of Medicine and director of the USC Eye Institute.
"It's not that the child is not smart enough or bright enough, it's that they see the world a little differently," Dr. Varma said.
According to Dr. Varma, children with color blindness can benefit from different kinds of lesson plans or homework to demonstrate their understanding of concepts despite their inability to see colors correctly. "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 added.
For more information on color blindness, visit www.geteyesmart.org.
Studies published in the April 2014 print issue of Ophthalmology include:
Environmental Factors Affect the Risk of Dry Eye Syndrome in a United States Veteran Population
In this study of more than 600,000 U.S. Veterans diagnosed with dry eye, air pollution and atmospheric pressure emerged as the most influential predictors of dry eye syndrome. Patients in the urban areas Chicago and New York City were three to four times more likely to be diagnosed with dry eye syndrome compared with less urban areas.
Incidence, Types, and Lifetime Risk of Adult-Onset Strabismus
The lifetime risk of developing adult-onset strabismus, or cross-eyes, was 4 percent, the incidence increasing with advancing age. Paralytic strabismus and convergence insufficiency comprised 60 percent of cases.
About the American Academy of Ophthalmology
The American Academy of Ophthalmology, headquartered in San Francisco, is the world's largest association of eye physicians and surgeons — Eye M.D.s — with more than 32,000 members worldwide. Eye health care is provided by the three "O's" – ophthalmologists, optometrists, and opticians. It is the ophthalmologist, or Eye M.D., who has the education and training to treat it all: eye diseases, infections and injuries, and perform eye surgery. For more information, visit www.aao.org.
Ophthalmology, the official journal of the American Academy of Ophthalmology, publishes original, peer-reviewed, clinically applicable research. Topics include the results of clinical trials, new diagnostic and surgical techniques, treatment methods technology assessments, translational science reviews and editorials.