Self-administered automatic sight-testing. A feasibility study.

A feasibility study to estimate the extent to which self-administered computerized sight-testing instruments would be acceptable to patients and staff in a hospital outpatient eye department has been carried out. Visual acuity was measured in two ways for each of 86 patients in the age range 20-79 years; Snellen acuity was compared with the screen-based Landolt C test. The patient was seated in front of the computer controlled display, supplied with tape-recorded instructions: his/her progress was monitored without intervention unless there were obvious difficulties. The mean acuities as measured by the two methods did not differ significantly from each other, with similar variances. More than 70% of patients managed the self-administered test without any help at all, only 4-5% failing completely. The computerized test was favoured by most except the oldest patients. It forms therefore a sound basis for further development on a large scale.