WEDNESDAY, Feb. 21, 2018 (HealthDay News) -- For students, an undetected vision problem could be contributing to low grades, a new study suggests.
That could be the case even if standard eye tests reveal no problems, the researchers said.
"It's not just about visual acuity, but about how well the eyes work together when performing an activity such as reading," said lead researcher Lisa Christian. She's an associate clinical professor in the School of Optometry and Vision Science at the University of Waterloo, in Canada.
Participants in the study included 121 children, aged 6 to 14 years, who were getting extra help for reading. More than three-fourths of the children had 20/20 vision, according to standard vision tests.
However, more than one-third had lower-than-normal scores on tests of binocular vision, the investigators found. That's when the two eyes work together to create a single visual image.
"A complete binocular vision assessment is not always part of the standard vision test. However, binocular vision problems could be compounding a child's academic difficulties, and should be investigated," Christian said in a university news release.
"Kids can see words on the page, but if they have difficulty turning their eyes in to read or focusing words on a page, they may experience symptoms of eye strain, double vision or fatigue after five or 10 minutes," she explained.
"Full eye examinations -- particularly in children with vision issues -- may be a tool for parents and educators to assist children who are found to have difficulty reading," Christian said.
The study was published online recently in the Journal of Optometry.
The American Optometric Association has more on children and vision problems.