Measurement of visual acuity with two different charts; a comparison of results and repeatability in patients with cataract.
OBJECTIVE
To compare two different optotypes to measure visual acuity.


METHODS
Experiment 1: Fifty patients with moderate cataracts were asked to read a chart consisting of letters of the alphabet (Sloan letters) first and a chart comprising Landolt's broken rings afterwards. Experiment 2: Half of patients were instructed to repeat the reading with a second letter chart, the other half was instructed to read the chart with the broken rings again.


CONCLUSIONS
Experiment 1: It was found that with the letter chart more optotypes (two to four) were recognized than with the broken ring chart. The different result of visual acuity measurement with the two optotypes is irrespective of the visual acuity. Experiment 2: The re-read instruction revealed that the measurements were reproduced equally for both charts.
van den Brom
H J
HJ
Department of Ophthalmology, University of Groningen, The Netherlands.
Kooijman
A C
AC
Blanksma
L J
LJ
van Rij
G
G
D002386:Cataract / Q000503:physiopathology*; D006801:Humans; D015203:Reproducibility of Results; D014787:Vision Tests / Q000379:methods*; D014792:Visual Acuity / Q000502:physiology*