New iPAD-based test for the detection of color vision deficiencies

To develop and validate a new iPad-based color vision test (Optopad). A total of 341 student eyes were enrolled in a first comparative study between Optopad and the Isihara tests. In a second comparative study, Optopad vs. the Farnworth-Munsell test (FM 100H), a total of 66 adult eyes were included. Besides the agreement between tests, the correlation between FM 100H and Optopad outcomes were investigated. Multiple regression analysis was used to predict the total error score (TES) from contrast thresholds measured with the Optopad test. The Ishihara and Optopad tests detected the same anomalous patients. Concerning FM 100H vs. Optopad, 10 subjects were diagnosed as anomalous with both tests, 3 mild anomalous cases based on TES were classified as normal with Optopad, and 2 anomalous subjects based on Optopad test showed normal TES values. Statistically significant correlations of TES and partial error red-green (PTESRG) with thresholds measured with the red-green Optopad stimuli were found. A multiple quadratic regression model was obtained relating TES and chromatic contrast values from Optopad (R2 = 0.855), with only 13 cases showing residuals of ≥ 25 units. The design and implementation of a chromatic contrast discrimination test has been carried out, with promising clinical results. This test seems to provide comparable outcomes to those obtained with Ishihara and FM 100H tests.