Introduction to Usability Testing
Carolee Mitchell
The University of Texas Libraries
Introduction
- About Digital Library Services Division
- History of Usability at UT Libraries
- 2000 Redesign of UT Library Web Site
- 2003-2004 Redesign of UT Library Web Site
- Other Library Sites
- UTOPIA
- Partnerships
- Accessibility Institute
- School of Information
Why Test Usability?
In order for a web site to be successful, it must be usable - target users
must be able to accomplish tasks with little or no difficulty.
Usability testing enables web developers to understand audience needs and,
in return, produce stronger and more effective sites well worth the money
and time that is put in their development.
In a perfect world...
Testing should not start after a site is in production.
Usability should be taken into consideration from the initial development
stages and become an iterative process that continues through the life of
a site.
Types of Usability Assessment
(In order from most affordable/quick to most costly/time intensive)
- Heuristic Evaluation
- Prototype Test
- Card Sort Activity
- Usability Test
Heuristic Evaluation
In a heuristic evaluation, a web site is tested against an established set of usability heuristics.
(Think "best practices")
For example:
Does the site have consistent navigation?
Do link terms make sense?
Do images have alternate text?
etc...
Heuristic Evaluation - Resources Needed
- Staff
One observant and detail-oriented staff member who likes to do research.
Many times having two or three people available to look over the site
can result in a more complete report.
- Time
Varies.
- Number of Participants
None
- Participant incentives
n/a
- Facilities
Your office.
- Equipment
Computer, word processing software or email program, well-rounded collection
of usability, accessibility, and information architecture books - or access
to a library
Prototype Test
A web site does not have to be completed and in production before you get valuable
feedback.
Prototype sessions can be performed using:
- a site wireframe (high-fi)
- printout of a design
- a line drawing on a piece of paper (low-fi)
Sessions can be held with groups or individuals, in an office or outside on campus.
Prototype Test - Resources Needed
- Staff
One person can prepare materials, set up and lead sessions, and compile
results. Having more staff available to assist
and observe doesn't hurt.
- Time
A 45 minute session with a group of users, or a few minutes if one-on-one
- Number of Participants
Varies
- Participant incentives
If a group setting, snacks or pizza. For individual sessions, little prizes (pens, pencils, etc...) may help get attention.
- Facilities
If a group setting, an office or conference room. If doing as a field test, none.
- Equipment
If indoors, a computer with projector. Printed copies of the site and colored pens work just as well.
Card Sorting
When dealing with the organization, naming conventions and functionality
of navigation, card sort activities can be extremely useful.
In a card sort activity, participants are:
- Given a stack of cards with terms written on them
- Asked to place the cards into what they consider logical groupings
- Asked to come up with titles for the groups
Card sorting can help web developers discover new ways to organize information or solutions to navigational challenges.
Card Sorting - Resources Needed
- Staff
Sessions can be led by one staff member, but assistance
will help when working with larger groups.
- Time
A session can take from 30 minutes to 2 hours, depending on number of
participants.
- Number of Participants
From 3-15, depending on if using individuals or groups.
- Participant incentives
If there is a budget, gift certificates or snacks.
- Facilities
An office or conference room with large tables
- Equipment
Cards labeled with terms, post-it notes, pens, large paper to tape on final
results for revisiting and report writing.
Usability Test
A formal usability session is the best way to find out how users interact
with a site.
In a usability session, a user is observed while navigating a site to
perform specific tasks.
A usability test can be broken down into the following steps:
- Pre-Session Activities
- Session Activities
- Post-Session Activities
Pre-Session Activities
- Identify stakeholders
- Work with stakeholders to develop list of tasks and goals for the
sessions
- Check with the school's research ethics office for human research subject permissions/restraints
- Recruit and schedule participants
- Put together test materials
Session Activities
- Welcome participant
- Give pre-test questionnaire and permission form
- Begin tasks - Ask to think aloud as they go through the tasks
- Ask "what are you thinking?" or ask follow up questions
- Keep track of time to complete each task
- Take notes - most important part of usability assessment
- Give post-test questionnaire and debriefing
Post-Session Activities
- Transcribe notes
- Put together "brainstorming" list of issues after all sessions are
complete
- Write report
- Share findings with web developers and stakeholders
Components of a Usability Test
A usability test packet should include the following items:
- Script
- Permission form
- Pre-test questionnaire
- Tasks (8-10)
- Post-test questionnaire
Usability Test - Resources Needed
- Staff
It is preferable to have 2 staff members - one to proctor the session
and another to take notes and keep time
- Time
30 minutes to an hour per participant
- Number of Participants
8-15
- Participant incentives
$5-$20 gift certificate per participant. Bottled Water and snacks
- Facilities
Quiet office or testing facility
- Equipment
Minimum: computer with browser, stop watch, pen and paper
Big time: Testing Facility that includes computer, camera, screen capture
or testing software, VCR, 2-way mirror, microphone system
A Note on Participants
KNOW YOUR AUDIENCE!!!
Tests focused on an inaccurate audience can be harmful to site usability.
Participant recruitment can be the most challenging and
frustrating part of any usability test - incentives help.
Accessibility
Usability refers to all members of a user group
According to the 2000 US Census, 1 in 5 people over the age of 5 has a disability.
A web site should be as usable for users with disabilities as those without.
It's the Law
Section 508 of the Rehabilitation Act of 1973 requires that all state and
Federal agencies' electronic and information technology is accessible to
people with disabilities.
“State Web sites shall meet the definition of generally accessible
Internet site, and ensure that all web pages transform gracefully and remain
accessible despite any physical, sensory, or environmental constraints or
technological barriers.” (Texas
Administrative Code, Title 1, Part 10, 206.2 (a)(2).
Useful Reading: Book List
- Usability
- Garrett, Jesse James. The Elements of User Experience: User-Centered Design for the Web. New Riders Press. 2002.
- Krug, Steve. Don't Make Me Think: A Common Sense Approach to Web Usability. New Riders Press. 2000.
- Nielsen, Jakob. Designing Web Usability: The Practice of Simplicity. New Riders Press. 1999.
- Rosenfeld, Louis and Peter Morville. Information Architecture for the World Wide Web: Designing Large-Scale Web Sites. O'Reilly. 2002.
- Rubin, Jeffrey. Handbook of Usability Testing: How to Plan, Design, and Conduct Effective Tests. Wiley. 1994.
- Wodtke, Christina. Information Architecture: Blueprints for the Web. Pearson Education. 2002.
- Accessibility
- Paciello, Michael G. Web Accessibility for People With Disabilities (R & D Developer Series). CMP Books. 2000.
- Slatin, John and Sharron Rush. Maximum Accessibility: Making Your Web Site More Usable for Everyone. Addison-Wesley. 2002.
- Thatcher, Jim et. all. Constructing Accessible Websites. Apress. 2003.