Kids with a wandering eye are less likely to be invited to birthday parties than their peers with normally aligned eyes, a new study suggests.

The researchers suggest such findings support the idea that corrective eye surgery should be performed no later than the age of 6, which is when the discrimination seems to emerge.

Strabismus, also called wandering eye, deviating eye, eye squint and crossed eyes, is different from lazy eye and is caused by a lack of coordination between the eyes, resulting in the eyes looking in different directions rather than focusing on a single point, according to the National Institutes of Health. Parents sometimes notice the disorder because children will squint or cover one eye when looking at an object, according to Merck, the online medical library.

The findings suggest such an eye disorder can have a lasting psychological impact on the individual, and that "visible differences in general have a negative impact on how children are perceived by peers," the researchers note in a report published online in the British Journal of Ophthalmology.

The researchers digitally altered photos of six children from six identical twin pairs to create inward and outward types of strabismus to compare against normally aligned eyes. Then, 118 children ages 3 to 12 who had normally aligned eyes looked at the images and had to select which of the identical twins they would invite to their birthday party. The participants were patients at an eye clinic or the siblings of patients.

The kids were shown four pairs of pictures, giving them the chance to select the faces of up to four children with a squint. If the eye disorder were to make no difference in their selection, the researchers would expect the kids to choose to invite two children with squints on average.

The children under 6 didn't make any distinction between the twins with and without a squint. But children ages 6 and older were significantly less likely to choose pictures of children with a visible squint.

Among the 48 children ages 6 to 8, 18 didn't "invite" any child with a squint; 17 chose a child with a squint once; 11 did so twice; two did so three times. None did so four times.

This compares with 31 children ages 4 to 6, one of whom didn't select any child with a squint, and 21 of whom did so once or twice. Nine did so three or four times.

When asked if they had noticed anything particular about the twins, around 19 percent of 4- to 6-year-olds commented on eye alignment, a figure that rose to 39 percent after being asked to pay attention to the eyes. Among 6- to 8-year-olds, 48 percent noticed the squint, which rose to 77 percent after being asked to pay attention to the eyes.

The results held after other factors seen in the photos, such as the color of the child's shirt, gender, or the type of squint, were taken into account.

This article was reprinted with permission from LiveScience.

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