New Test Could Help Detect Children’s Vision Issues Earlier
Wednesday, August 27 2025 | 08 h 08 min | News
Testing visual acuity in young children has long been a challenge, as traditional eye charts rely on letter recognition. For children too young to read, subtle vision problems often go undetected until later years — reducing opportunities for early intervention.
Dr. Susan Leat, a professor at the University of Waterloo, is aiming to change that. With funding from Fighting Blindness Canada, Dr. Leat and her team have developed the Waterloo Differential Acuity Test (WatDAT), designed specifically for children under the age of three. The test is currently in Beta trials.
Instead of reading letters, children play a simple “odd-one-out” game: they are asked to point to the picture that looks different from the others. This approach has proven both intuitive and effective for very young patients.
In recent studies, 96% of children between 18 months and 4 years old were able to complete the test, and results closely matched the gold-standard tests used in adults. WatDAT may be capable of detecting up to 96% of vision deficits at an earlier age than ever before.
Both digital and printed versions of WatDAT have been created, and independent optometrists across Canada are now evaluating the tool in real-world clinics. If successful, the test could soon be widely available to eye care professionals.
Dr. Leat notes that early detection of vision problems is critical: untreated vision loss in early childhood can affect motor skills, learning, and long-term opportunities. She emphasizes that the project would not have been possible without the support of Fighting Blindness Canada.
WatDAT represents a potential breakthrough in pediatric eye care — giving optometrists the ability to identify and address vision concerns in children long before they can say, “I can’t see.”
Source: Fighting Blindness Canada
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