03. Understanding the diversity of users

INSTRUCTOR NOTE:

Some statistics on disability for the US:

• Around 2% of the population has some kind of vision disability (i.e. are blind or have significant difficulty seeing even with glasses)
• Around 50% of the population has some kind of clinically significant refractive error (a visual impairment which may be corrected with glasses if mild enough)
• Around 8% of males and 0.5% of females have some form of color vision deficiency
• Around 2% of adults have a hearing disability
• Over 4% have a cognitive disability (difficulty remembering, concentrating, or making decisions)

Sources:

• Disability Compendium
• "The Perception of Color"
• "Prevalence of Refractive Error in the United States, 1999-2004"