Results of the Oscar Test in Groups of Normal and Abnormal Subjects

The mean OSCAR setting presents in normal subjects a significant age-related shift to more positive values. It is significantly and still more shifted to negative values in protan heterozygocity, protanomaly and protanopia. It is significantly and still more shifted to positive values in deutan heterozygocity, deuteranomaly and protanopia. The test distinguishes all cases of protanopia and some cases of the other conditions (including heterozygocity) from normal color vision. The practical use of the test will be to distinguish protan and deutan types from among affected homozygotes (detected e.g. by means of the Ishihara test) as well as from among heterozygotes (with normal color vision). The flicker-free zone of the scale is much enlarged in typical achromatopsia. It is still not evident if the test could be useful in the diagnosis of acquired color vision defects.