The Ishihara Color Test is designed specifically for those with red-green color deficiencies. It cannot detect other deficiencies, such as the rarer blue colorblindness. When compared to other colorblind tests, the Ishihara Color Test has a highly discriminate accuracy, but it is less accurate than the HRR color test.
The Hardly-Rand-Ritter pseudoisochromatic color test has been tested to perform at the same level as the Ishihara test between patients of similar cone dystrophy and color blindness. Within patients who have normal to poor vision, but no history of colorblindness, the HRR test is more effective at determining differences in color perception.