Reliability of a standardized test in Swedish for evaluation of reading performance in healthy eyes. Interchart and test-retest analyses.

Purpose The purpose of our study was to establish a practical and quick test for assessing reading performance and to statistically analyse interchart and test–retest reliability of a new standardized Swedish reading chart system consisting of three charts constructed according to the principles available in the literature. Methods Twenty-four subjects with healthy eyes, mean age 65 ± 10 years, were tested binocularly and the reading performance evaluated as reading acuity, critical print size and maximum reading speed. The test charts all consist of 12 short text sentences with a print size ranging from 0.9 to −0.2 logMAR in approximate steps of 0.1 logMAR. Two testing sessions, in two different groups (C1 and C2), were under strict control of luminance and lighting environment. Reading performance tests with chart T1, T2 and T3 were used for evaluation of interchart reliability and test data from a second session 1 month or more apart for the test–retest analysis. Results The testing of reading performance in adult observers with short sentences of continuous text was quick and practical. The agreement between the tests obtained with the three different test charts was high both within the same test session and at retest. Conclusion This new Swedish variant of a standardized reading system based on short sentences and logarithmic progression of print size provides reliable measurements of reading performance and preliminary norms in an age group around 65 years. The reading test with three independent reading charts can be useful for clinical studies of reading ability before and after treatment.