Defining accessibility
At STC 2006, I’ll be talking about the parallels between accessibility and usability, a subject previously tackled by Dey Alexander, among others. I write in the hopes of better defining accessibility and ensuring that the problems I’ve written about with usability (extreme usability) don’t happen with accessibility as well. I don’t think we should to assume that “discount accessibility,” which is the direction some folks are heading in, will work the same way as “discount usability,” which is overall a pretty viable concept.
Most often, comparisons between the two are made in the hopes of selling folks who’ve already bought into usability on accessibility. The assumption here is that folks are interested enough in improving usability to invest time in accessibility. However, sometimes accessibility and usability are conflated destructively: assuming they are close enough to be called “accessibility/usability” obliterates the context of use which is necessary for effective usability evaluations (since usability is best defined with a specific task orientation) as well as for variations in accessibility audiences (low-vision users need different affordances than those with motor skill problems).
Other parallels aren’t necessarily deliberate. In this class I put the tendency to see both accessibility and usability outside of the “regular” development process—extras which are considered for dumb or disabled audiences, as well as casting both as a technological problem (throw enough resources and/or high-tech designs at a software application or a web site, and it’ll be just fine). While I think there’s been progress towards an integrative approach which acknowledges the complexity of accessibility and usability, without a doubt, for many, both concepts are still techie add-ons.
As I’ve written before, I like complex definitions of usability, like classical definitions from Dumas and Redish, and more recent formulations, like Whitney Quesenbery’s “five dimensions.” Perhaps we need a similar “dimensional” definition for accessibility?
So right now I write that “more research is needed”—both on my part and for accessibility practitioners, for whom methodological questions are far from settled.
