Verriest's classification of acquired colour vision anomalies
| Name | Alternative names | Colour discrimination defect | Visual acuity |
| Type I | Acquired R-G, protan-like | Mild to severe confusion of R-G hues, little or no loss of B-Y CD | Moderate to severe reduction |
| Type II | Acquired R-G, deutan-like | Mild to severe confusion of R-G hues with a concomitant mild loss of B-Y CD | Moderate to severe reduction |
| Type III | Acquired B-Y, tritan-like | Mild to moderate confusion of B-Y hues with a lesser impairment of R-G CD | May be normal or moderately reduced |
R-G = red-green, B-Y = blue-yellow, CD = colour discrimination.