Repeatability of Cone Contrast Color Vision Tests

New computerized color vision tests are gaining popularity in the aviation community. These tests determine color vision status by measuring chromatic sensitivity and they can effectively classify color vision as normal vs. abnormal. However, little information is available regarding their repeatability. We evaluated the repeatability of two such tests: the Operational Based Visual Assessment Cone Contrast Test (OCCT) and the Rabin Cone Contrast Test (RCCT).

A total of 56 subjects with normal color vision and 63 subjects with defective color vision completed both tests twice over 2 sessions. We determined the repeatability for a normal/abnormal result, between-eye differences in thresholds within a session, and between-session results for each eye.

Both tests had excellent repeatability for normal vs. abnormal color vision (i.e., using a cutoff score of 75 Rabin Color Contrast Sensitivity Units). The OCCT also had excellent repeatability for acceptable vs. unacceptable color discrimination (i.e., a cutoff score of 55), whereas the RCCT repeatability was lower. The RCCT's lower repeatability was because the between-eye and between-session Limits of Agreement for the color-defective subjects were approximately ±40 relative sensitivity units. In contrast, the Limits of Agreement for the OCCT ranged from ±10 to ±15.

These results reinforce the advantage of using a finer stimulus change when estimating cone thresholds in the clinical setting. Hovis JK, Almustanyir A, Glaholt M. Repeatability of cone contrast color vision tests. Aerosp Med Hum Perform. 2025; 96(4):287-295.