Team Usability develops methods for accessibility and usability testing
, by Detlev Fischer
Team Usability recognises the need for a stronger involvement of people with disabilities in accessibility evaluations. The project therefore sets out to develop two methods for accessibility and usability testing.
The expert test ("Praxis-Test")
The first method is the expert test (in German, we have chosen to call it "Praxis-Test" because it is based on the practical skills of testers with disablities involved). The expert test focuses on people with disabilities as expert testers. Testers need a good command of the assistive technologies they use. They also need to develop a good understanding of general accessibility requirements so they can cover the testing of all accessibility criteria—where necessary with the help of another member of the team.
Different expert test scenarios will be explored. The project team will explore how a blind and a sighted user, both members of the core project team, can work together in carrying out standards-based conformance tests of web content and native apps. It is clear that some aspects impacting accessibility, like contrast, magnification, or reflow, are difficult or even impossible to test for a blind tester. Here, co-operation in the team kicks in.
Another scenario is a group of people with mental illnesses whose members are usually not users of assistive technology but may have various conditions impacting on modes of learning and working. This could concern the degree of attention or focus on the task at hand, and workable modes of communication with other team members. In this scenario, the focus is on identifying suitable work conditions and usable approaches for establishing a sustainable accessibility competence in the team, and measures needed to safeguard the quality of results.
The method thus covers organisational and social aspects, aspects of learning, and technical aspects related to the application of established test procedures such as BITV-Test. We will draw on the results of the scenarios we are piloting as well as on best practices gathered from carrying out case studies with partners that already involve people with disabilities in their testing.
The usability test
The second method to be developed is the usability test. Common usability tests of web content and applications, as far as they happen at all, mostly focus on the average user, not on people with disabilites. Our method departs from common usability testing approaches, but focuses on lay users with a disability. e intend to develop a task-based process that is flexible enough to accommodate users with very different disabilities.
The process should help to identify the particular usability issues users face when carrying out simple, clearly defined tasks. Test facilitators capture the problems that users encounter, which are often, but not always, down to accessibility issues. By testing the same tasks with different users with different disabilities, a picture emerges of the overall usability and accessibility of the task (and the site that contains it). It also becomes clearer to what extent the usability hinged on the (lack of) adherence to accessibility standards, and what other factors impacted on the usability observed in the tests.
We hope that the results will identify requirements that can be considered for inclusion in future versions of accessibility standards like WCAG. Other aspects are likely to suggest best practices or may fall under general usability issues affecting all users.
The usability test method focuses on developing a good workflow for task-based tests with different types of users. Another aspect is the attempt to create a richer picture of the actual accessibility of content that can complement and qualify the results of standards-based conformance tests.