Reference values for the Teller Acuity Cards II (TAC II) in infants and preverbal children, a meta-analysis

PurposeThe Teller Acuity Card (TAC) procedure is a preferential-looking method to assess visual acuity in infants and preverbal children and provides a quantitative measure of grating acuity. Several studies containing reference values have been published, the majority based on an older version of the TAC card set. In 2003, a new version of the TAC was released, called the TAC II. This study aims to provide clinicians with a unified set of age norms for the TAC II.MethodsWe conducted a literature search and extracted individual data points per age from either tables or figures. We performed a weighted regression on both the standard deviation and the mean visual acuity as a function of age. Furthermore, based on literature, we corrected data points from studies using the original TAC by subtracting 0.3 octave to align them with the TAC II age norms.ResultsA total of 5 studies, published between 1990 and 2006, provided binocular visual acuity data for 837 children and monocular visual acuity data for 1052 children. Age norms were derived from these combined data sets.ConclusionsThe TAC charts are the gold standard for assessing visual acuity between the ages of 0 and 36 months. We provide a unified set of age norms for TAC II, the most recent version of the TAC charts.