An improved vision test for toddlers

Researchers from the University of Waterloo in Canada have outlined their efforts to develop a new vision test for toddlers in Ophthalmic and Physiological Optics.

The Waterloo Differential Acuity Test (WatDAT) involves showing young children four shapes. Three of the shapes are identical, with the child directed to point at the shape that is different.

The test is performed with progressively smaller shapes until the child can no longer identify the shape that is different.

As part of the study, researchers assessed visual acuity in 57 children between the ages of 18 and 48 months using WatDAT.

Compared to two other paediatric vision tests currently in use (Patti Pics and Kay Pictures), more children were able to complete WatDAT at younger ages. All three tests took a similar amount of time.

The researchers found that the test worked for all study participants meeting developmental milestones who were 24 months and older.

Many children who were 18 months and older could also complete the WatDAT assessment.

Study lead, Professor Susan Leat, of the University of Waterloo, highlighted that many vision problems in childhood – such as amblyopia and astigmatism – are not obvious from simply observing a child.

“If this test becomes available in clinics, it will allow eye doctors to detect vision disorders earlier, leading to more effective treatment.”

WatDAT is currently subject to beta testing by optometrists in Canada, the US and UK. The researchers intend to commercialise the test after beta testing is completed.