Capsule: The roots of cross-eyed bias

By Karen Kaplan, Los Angeles Times People with strabismus, better known as being cross-eyed, face many hurdles aside from their vision. Studies have shown that adults with the condition are less likely to be in a romantic relationship, less likely to have a job and more likely to have “psychosocial problems.” One study of elementary school teachers found that they were biased against kids with the condition, scoring them lower than normal children on measures of health, happiness and ability to work hard.

When does this bias set in? To find out, Swiss researchers used Photoshop to create pictures of “twin pairs” in which one twin had normal vision and the other had eyes that were misaligned. (In reality, both pictures were of the same child, with one photo digitally altered.) Then they showed these pictures of fake twins to 118 kids ages 3 to 12 and asked a straightforward question: Which twin would you invite to your birthday party?

Each study participant was shown pictures of four sets of twins. If strabismus wasn’t a factor, then on average each child would invite two cross-eyed kids to their birthday party and two with normal eyes.

For children younger than age 6, that’s exactly what researchers found. But for participants ages 6 to 12, the number of birthday party invitations going to kids with strabismus averaged slightly less than one.

The 6- to 8-year-old age group marked a clear turning point in attitudes toward kids with the condition. Children ages 4 to 6 noticed that some of the twins were cross-eyed, but that difference didn’t translate into fewer birthday party invitations, according to the study, which was published online Wednesday by the British Journal of Ophthalmology.

Based on the results, the Swiss researchers recommended that corrective surgery for strabismus should be performed before children turn 6 to avoid the “negative social implications” that accompany the condition.

karen.kaplan@latimes.com