Certified Professional in Accessibility Core Competencies (CPACC) Practice Exam

Red and green color blindness is the most prevalent form of color blindness among individuals, affecting a significant portion of the population. This type of color vision deficiency is often linked to genetic factors, particularly in males, where the condition arises due to variations in the X chromosome.

Estimates suggest that about 8% of men and 0.5% of women of Northern European ancestry have red-green color blindness, making it far more common than the other types listed. The deficiency primarily involves the inability to distinguish between reds, greens, and browns, which can impact daily activities and recognition of traffic lights, for example.

In contrast, blue and yellow color blindness is considerably rarer, and complete color blindness, also known as achromatopsia, is an even less common condition where an individual perceives the world only in shades of gray. These forms of color blindness generally occur in a much smaller percentage of the population, contributing to the established understanding that red and green color blindness is the most widespread.