Vision Screening with a Microcomputer:  Validation of Two Computerized Acuity Tests

B.D. Johnson; M.J. Samak

doi:10.65636/cjo.v51i3.7020

Authors

B.D. Johnson
M.J. Samak

DOI:

https://doi.org/10.65636/cjo.v51i3.7020

Keywords:

vision screening, microcomputer, accuity test

Abstract

The purpose of this study was to evaluate two computerized acuity tests which represent part of a battery of computerized assessment procedures that may be used for vision screening. Habitual monocular acuities of 20 subjects were evaluated using eye charts generated by a microcomputer. In one procedure (AC), subjects were asked to identify alphabetical characters ranging in size from 6/24 (20/80) to 6/6 (20/20). In the other procedure (TE), subjects were asked to identify illiterate E characters, which were shown over the same acuity range. The results of the computerized procedures were compared to acuity measurements obtained using non-serifed Snellen charts. Both computerized tests were validated. A regression analysis revealed that the computerized estimates of visual acuity differed from the clinical measurement by one optotype, given five, at the threshold level. Since both the alphabetical and illiterate E characters produced similar and valid results, it is suggested that the present tests may be of value for screening visual acuity in reading and nonreading groups.

References

1. Timberlake, George, Mainster, Martin A, and Schepens, Charles L. Automated Clinical Visual Acuity Testing. American Journal of Ophthalmology. Vol 90: 369-373. 1980. DOI: https://doi.org/10.1016/S0002-9394(14)74918-9

2. Friendly, David S and Wiess, Ira P. An Automated Visual Acuity Testing Computer Program Using the Apple II System. American Journal of Ophthalmology. Vol 99: 188-192. 1985. DOI: https://doi.org/10.1016/0002-9394(85)90231-4

3. Allen, Merrill J. Accommodative Rock via Computer. Journal of the American Optometric Association. Vol 59(8): 610-613. 1988.

4. Yeager, Dwayne and Boltz, Roger L. Computerized Fixation Disparity Measurement. American Journal of Optometry and Physiological Optics. Vol 63(8): 654-661. 1986. DOI: https://doi.org/10.1097/00006324-198608000-00009

5. Edworthy, GA. An Evaluation of the Microcomputer as a Vision Screening Medium. Canadian Journal of Optometry. Vol 47(4): 157-161. 1985. DOI: https://doi.org/10.15353/cjo.v47i4.4458

6. Payor, Rick. Performance of Video-Displayed Letter Charts. Clinical and Experimental Optometry. Vol 69(2): 73-76. 1986. DOI: https://doi.org/10.1111/j.1444-0938.1986.tb04572.x

7 . Personal communication, meeting with representatives from Peel Region Public Health Dept., City of Toronto Public Health, and Etobicoke Public Health Dept, August, 1988.