Accessibility Vocabulary

[MRuecklCC]

Currently, the accessibility vocabulary holds 5 different choices:

• A
• AA
• AAA
• WCAG
• BITV

Unfortunately, I was not able to find any documentation about when exactly use which choice. Reading about BITV and WCAG, I found that BITV seems to be a superset of the WCAG AAA rating, i.e. if a site is BITV compliant it would also have a AAA WCAG rating. This makes the current definition of the value space slightly confusing:

• Why is there a WCAG value?
• There is no value for "not even A", i.e. a site that does not fulfill even the lowest standards,
• We could change to (in ascending order):
  • B (or some other name, no compliance)
  • A (WCAG)
  • AA (WCAG)
  • AAA (WCAG)
  • BITV

IMHO, it is very important to distinguish the scenario, where a rating is not available (missing meta-datum) and where a site is not compliant with any rating (currently also a missing meta-datum), so we should definitively add a "B" rating value.

[lummerland]

I agree, the A-ratings belong to WCAG so there is no need for the extra value. BITV, for one, has 2 levels (Priorität 1 + 2) that maybe should be taken into account here as well? I find the distinction "no rating" and "low rating" very useful, actually there is only a "no rating" available.
Why not propose a change via pull request? :)