Tritan Epidemic
In literature, the prevalence of Tritans (<1/3000) is much lower than for Red-Green Colorblindness (~1/25). However, the number of self-reported Tritans in Colorblind communities is on par with the Protans and Deutans. This discrepancy comes down to several factors:
- Tritans were previously underdiagnosed. Tritan defects are often considered ‘less severe’ than red-greed defects because naturally and culturally, the red-green channel is more important. That means red-green defects are generally noticed quickly by someone who has one and diagnosed. The cultural significance (jobs requiring red-green vision) also means that tests were ubiquitous long ago (see Holmgren’s Wool). It took much longer for Tritan tests to become available and they have never been used extensively for job screening, so while the rates of prevalence in literature were being defined (1960’s), Tritans were simply not being diagnosed.
- Because Tritan tests are mostly self-administered and taken on a screen, they are prone to error due to the accuracy of the screen’s color representation. For example, if a Tritan test is taken on a phone with a blue-blocking (i.e. nighttime) filter, this introduces a Tritan defect that will cause a Color Normal to be diagnosed as a Tritan.
- Similar to the Myopia epidemic, there may be an actual increase in the prevalence of Tritan CVD in the last 50 years due to environmental factors, e.g. because it is a common side effect of many types of drugs (e.g. Viagra).