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Re: System Usability Scale with Blind/VI users

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From: Tim Harshbarger
Date: Sep 8, 2015 9:52PM

SUS is definitely something that could be used as part of usability testing with people of any type of disability.

However, the one thing I would urge that you keep in mind is that it measures the user's perception of the system's usability--which is not necessarily the same as the reality of how usable the system is. That isn't to say that there is no value in using SUS. It is just important to keep in mind what SUS really measures.

I tend to think of accessibility and usability as a weird type of pyramid. At the bottom you have accessibility. If you don't have accessibility, you can't even really begin to address usability. From a task oriented perspective, until the tasks are accessible, you can't really even start to address issues such as accuracy or efficiency.

The weird aspect to the pyramid is that it isn't built of bricks. There isn't a layer of accessibility bricks at the bottom with usability bricks placed on the layer above. There isn't a clear cut division between usability and accessibility.

It is kind of like dawn. There is a point when it is clearly night. And there is a point when it is clearly day. But there is a transition between when it might be argued whether it is still day or night. I hope that makes some kind of sense.

Hopefully something I wrote is useful food for thought.

-----Original Message-----
From: WebAIM-Forum [mailto: <EMAIL REMOVED> ] On Behalf Of Karen Sorensen
Sent: Friday, September 04, 2015 12:34 PM
To: WebAIM Discussion List
Subject: [WebAIM] System Usability Scale with Blind/VI users

Hi Amelia,
I haven't used this scale, but I'll check it out. At Portland Community
College, where I work, we do accessibility testing of information and
communication technologies used or being considered for use at the college.
But recently we have been discussing the difference between accessibility
and usability testing. I think what we do often is actually usability
testing. Because although something can be considered accessible by a
vendor, if an experienced screen reader user cannot actually make it work,
then we have a problem. It may be that documentation could fix the problem
instead of a technical change but it's still valid feedback. Accessibility
and usability testing should always include people with a wide range of
disabilities as Ron advises.
Thanks!
Karen
Karen M. Sorensen
Accessibility Advocate for Online Courses
www.pcc.edu/access
Portland Community College
971-722-4720