Before revision: For children aged 1-2 years old, visual acuity can be tested by Worth’s ivory ball test, Boeck’s candy test, the Screening Test for Young Children and Retards, and Cardiff’s acuity test.
After revision: For children aged 1–2 years old, visual acuity can be tested by Worth’s ivory ball test, Boeck’s candy test, the Screening Test for Young Children and Retards, and Cardiff’s acuity test.