Development.
Accessibility Analysis.

A study to measure how the website is easy for everyone to use, regardless of their special needs. It could be done by specific tools, following the W3C guideline or even by an usability test.

AboutAuthorDate
Web Accessibility Evaluation Tools ListW3C
Accessibility testingW3C
What is accessibility Testing?Tutorials Point
Myth #5: Accessibility is expensive and difficultUX Myths
Web Accessibility Testingjimthatcher.com