Evaluation of usability of websites
This article is reprinted from Ragged Left, newsletter of the Berkeley chapter STC, September/October 2005. It is the review of the chapter’s August 2005 meeting by Ron Sands.
At the August 2005 Berkeley chapter meeting, Dana Chisnell of UsabilityWorks gave an interactive presentation on evaluation of usability using heuristics and personas. The presentation summarized the findings of two research papers she co-wrote with Janice (Ginny) Redish of Redish & Associates, Inc. Their research was commissioned by the American Association of Retired Persons (AARP). All quotations in this article are from the paper “Designing Web Sites for Older Adults: Expert Review of Usability for Older Adults at 50 Web Sites,” which is available for download at the AARP web site.
Dana began her presentation by giving some background on the subject of usability evaluation. She defined the term heuristics as “the art and science of discovery and invention.” This is distinct from the term algorithm, which is a step-by-step procedure. In the context of the research project, the heuristics they used were a set of 20 guidelines from four major categories of usability (see below). A complete description of the heuristics they used is available at the AARP web site.
She described personas as assumed roles, archetypes, or character sketches. Personas are more detailed than user profiles, taking into account the character’s age, marital status, day-to-day activities, and job tasks. The personas created for the research project emphasized four areas of diversity: age, ability, aptitude, and attitude.
She explained the methodology they used. They created a number of task lists to be performed by each persona at the websites being evaluated. They performed the evaluations in two phases. First, they channeled (pretended to be) a particular persona, performing the tasks on the task list, and recording their observations (actual experience, thoughts, and opinions). Next, as themselves, they repeated the actions of the persona, and graded their observations against the 20 usability guidelines in their heuristics.
Possible scores were 4 (no problem), 3 (minor hindrance), 2 (serious problem), and 1 (task failure). In the interactive portion of the presentation, audience members were asked to channel one of two personas. Some of us chose to be Matthew, a 54-year old attorney, working full-time whose attitude was described as, “When something doesn’t work right away, Matthew moves on. He doesn’t have the time or patience to figure it out.” Others chose to be Edith, a 73-year old retired grandmother, with very little experience using web sites. We were asked to perform one simple task: find information about Zocor on the AARP web site. As both personas, we found several instances where we graded the AARP web site as a 2 (serious problem) that could have been improved with the application of the guidelines.
The overall conclusion of the research project was that “the World Wide Web is not an inherently hostile place for older adults, though there are some ways that sites could do better to increase their usability for everyone.”
A summary of the heuristics follows.
Interaction Design • Use conventional interaction elements • Make it obvious what is clickable and what is not • Make clickable items easy to target and hit • Minimize vertical scrolling; eliminate horizontal scrolling • Ensure that the Back button behaves predictably • Let the user stay in control • Provide clear feedback on actions • Provide feedback in other modes in addition to visual
Information Architecture • Make the structure of the web site as visible as possible • Clearly label content categories; assist recognition and retrieval rather than recall • Implement the shallowest possible information hierarchy • Include a site map and link to it from every page
Visual Design • Make pages easy to skim or scan • Make elements on the page easy to read • Visually group related topics • Make sure text and background colors contrast • Use adequate white space
Information Design • Make it easy to find things on the page quickly • Focus the writing on audience and purpose • Use the users’ language; minimize jargon and technical terms