Which guideline includes Accessibility when using Nielsen's Heuristics?

Question

We've been tasked with performing a heuristic analysis for a project, and the requirements specifically include the use Nielsen's heuristics.

Although this isn't a problem for us, we usually use a reduced version of Kaniasty's criteria ( moved from the criteria of Bastien & Capin), since they contain a fairly complete criterion for accessibility.

Now I never noticed that Nielsen's heuristic doesn't include a clear heuristic criterion for accessibility (and neither does Shneidermann, although we've used "Keep Locus of Control" for accessibility).

In Nielsen's, the criterion that comes most readily to mind is # 6, "Recognition rather than recall."

So my question is: is this the right one? Or is there a better rule to group all accessibility concerns?

The Nielsen guidelines are so broad and vague that almost any guideline could fall under these accessibility criteria, so I'm not sure it's the right one.

Answer 1

I think the issue lies in the question. It assumes inclusion of accessibility in the heuristics, while you cannot treat accessibility as an isolated rule like the others. As we often say, accessibility is not a single person’s responsibility, neither can be handled as a phase or a last checkpoint.

There was some work done to map WCAG rules to Nielsen’s heuristics, which shows the nature of their relation. Accessibility is not one of the rules, but there’s a big overlap of what’s necessary for accessibility and the heuristics.

• The new WCAG 2.1 and Nielsen’s 10 Usability Heuristics
• Mapping WCAG Guidelines to Nielsen's Heuristics

So personally I would say that Nielsen’s heuristics are necessary but not sufficient for accessibility.

Answer 2

Accessibility touches all heuristics somehow but since you don't have a choice and need to put it somewhere...

About recognition rather than recall

Minimize the user's memory load by making elements, actions, and options visible. The user should not have to remember information from one part of the interface to another. Information required to use the design (e.g. field labels or menu items) should be visible or easily retrievable when needed.

This is more about repeating things, don't relying on the user's memory. But accessibility starts where the user learns about system status and offerings.

I would opt for visibility of system status:

The design should always keep users informed about what is going on, through appropriate feedback within a reasonable amount of time.

It can also be taken very broad. For example:

• On page load a screen reader reads the title and the context should be clear
• After page load the first thing to access is the menu to get informed about site structure and site offerings
• It is directly clear what's going on since all information has enough contrast and distinguishable colors

etc.