MONDAY, July 12 (HealthDay News) -- Eye chart tests reliably
detect nearsightedness in adolescents but not farsightedness or
astigmatism, according to a new study.
When Australian researchers assessed almost 2,400 students, with
an average age of just under 13 years, they found that the average
visual acuity score was 54 letters. The cutoff point of 45 letters
reliably spotted participants with nearsightedness (myopia), but no
reliable cutoff was found for either farsightedness (hyperopia) or
astigmatism (an abnormal curvature of the cornea that causes
difficulty focusing sharply, resulting in blurred vision).
The findings suggest that "many children with clinically
significant levels of hyperopia and astigmatism would not be
referred for treatment," wrote Jody Fay Leone, of the University of
Sydney, and colleagues in a JAMA/Archives news release.
The best visual acuity thresholds for detecting clinically
significant farsightedness and astigmatism "were 57 and 55 letters
or less, respectively, which equates to normal visual acuity of 6/6
or less, making the use of these thresholds quite meaningless," the
They said further research is needed to develop screening
methods that can reliable detect these eye problems in children and
The study appears in the July issue of the journal
Archives of Ophthalmology.
The Foundation of the American Academy of Ophthalmology has more