Accessibility Testing

Preliminary notes on accessibility testing. Rickybuchanan 13:04, 4 February 2009 (UTC)

Accessibility is not the same as usability, but it overlaps.

Some stuff can be tested automatically with tools - eg validation - but lots of it can't and comes down to human judgement. Good description here: What accessibility testing is possible Even they miss some stuff - contrast appropriate for dyslexics, moving image problems that people with some neuro deficits have, everything important being keyboard-only accessible. Probably more I forget.

Disabilities which have relevance to web accessibility:

Blindness
The one everybody thinks about.


 * CAPTCHAs
 * Screen reader friendliness (JAWS, WindowEyes, VoiceOver, NVDA, others?)
 * Check tab order for everything, especially things which are AJAXey

Deafness

 * Make sure any videos put on the site officially (eg "how to use" screencasts) have captions available.

Deafblindness
Double-whammy as many of the solutions to problems faced by blind or deaf users rely on the other sense - eg audio alternatives to CAPTCHAs.

Dyslexia

 * Contrast (too high can be a problem)
 * CAPTCHAs

Keyboard-only Users

 * Make sure anything triggered usually by mouse movements (eg :hover attributes) which is needed for site use has a keyboard-accessible alternative.
 * Check tab order for everything, especially things which are AJAXey

Low Vision

 * Contrast (low is a problem)
 * CAPTCHAs
 * Font size
 * Robustness of layout to font size increases (eg command-+/ctrl-+) under IE, Firefox, Safari, etc - they differ so need to test all.
 * Alternate layouts with less visual "clutter"/"noise" if needed (eg LJ's Lynx sitescheme)

Neurological Problems

 * Things that move
 * CAPTCHAs