Two hundred and twenty-nine adults were tested on a stereoscopic vision tester (Titmus) for visual acuity and color vision, and then with the 1970 edition of the Ishihara plates. The incidence of color defectives found was stereoscopic vision tester, 19.07%; Ishihara, 7.44%. The incidence reported in the literature is 8.38%. The incidence of color defective women found with the stereoscopic vision tester is significantly greater than that reported in the literature. No individual with visual acuity worse than 14/21 in either eye failed the Ishihara or both the Ishihara and stereoscopic vision tester. Many individuals who failed only the stereoscopic vision tester had visual acuity worse than 14/21 in at least one eye. After eliminating those individuals with visual acuity worse than 14/21 in either eye from the data, the results on the stereoscopic vision tester and Ishihara tests are nearly comparable.
Holland PM. Adult Color Vision ScreeningComparison of Stereoscopic Vision Tester Slide With Ishihara Plates. Arch Ophthalmol. 1972;88(6):613-616. doi:10.1001/archopht.1972.01000030615008