Conducting and
Using Usability Tests
Overview
What Is Usability
Testing?
Usability testing
encompasses a range of methods for identifying how users actually interact
with a prototype or a complete site. In a typical approach, users
one at a time or two working together use the Web site to perform
tasks, while one or more people watch, listen, and take notes.
Testing Goals
The goal of usability
testing is to find out what is and is not working well on the site (or
other product or service). In a usability test, you usually want to
answer questions like these:
- Do users complete
a task successfully?
- If so, how fast
do they do each task?
- Is that fast
enough to satisfy them?
- What paths do
they take in trying?
- Do those paths
seem efficient enough to them?
- Where do they
stumble? What problems do they have? Where do they get
confused?
- What words or
paths are they looking for that are not now on the site?
Types of Questions
to Ask
You might also have
more specific questions that are related to your site. For example:
- Do users realize,
without being told, whose site they are working with just from
looking at the home page?
- Do users click
through pages or do they use Search?
- What words do
they try in Search?
- What do they
choose from the Search results?
- How do they react
to the download time for specific pages?
- If they abandon
a shopping cart before buying, when do they stop and why?
Iterative Testing
Works Best
Usability testing
is an iterative process that involves testing the site and then using
the test results to change the site to better meet users' needs. The
best process is to try out a prototype with a few users, fix it, and
test it again.
Read more about:
Also see the sections
on usability testing in Usability Basics.
What
to Call It: Testing? Evaluation? Try Out?
In
the usability community, this technique is called "usability testing."
For users, however, "testing" often has negative connotations. We don't
want users to think that we are testing them. They are helping us test
the site. If something goes wrong, we fix the site we don't (and
can't) fix the users.
It helps if you
make sure you always think of the testing that way. Think "how well
is the site allowing the users to meet their goals" rather than "how
well do the users do on the site."
But it may help
even more if you change the word "testing" even in your own mind. Some
usability specialists like "usability evaluation" even though
it is a longer word than "testing" because it is softer.
An even better choice
might be "try out." We are asking users to come "try out" or "test
drive" a draft version of the site.
What
Are the Steps in Usability Testing and in Using the Results?
Under each step,
we list some questions or guidelines to consider in carrying out that
step.
1. Plan scope,
issues, participants, location, budget
- What are you
going to test?
- What concerns
do you have about the site that you want to test?
- Which users
should participate in the test?
- Where will
you conduct the test? In a fixed laboratory? In a conference room
or other space with a portable lab? In a conference room or other
space but without any recording equipment? Remotely?
- What is your
budget for testing?
For information
on fixed labs, portable labs, and recording equipment, see Usability
Labs.
For
information on remote usability testing,
see http://research.cs.vt.edu/usability/projects/remote%20evaln/
remote%20evaln.htm
2. Develop scenarios
- Select relevant
tasks for users to try.
- Prepare, try
out, and refine scenarios for those tasks.
Note: Make sure the scenarios are clearly written and not
too much of a challenge for the allotted test time.
3. Recruit test
participants
4. Conduct usability
testing
- Have a trained
facilitator interact with the user.
- Have trained
observers watch, listen, and take notes.
- Make sure participants
know that they are helping by trying out the Web site; the site
is being tested, not them.
- Get participants
to think aloud as they work.
- Let participants
express their reactions.
- Listen! Do
not lead. Be sure to stay neutral in your words and body language.
Be careful not to ask leading questions that may skew the participants'
responses.
- Take detailed,
useful notes concentrating on observations of behavior rather than
inferences.
5. Make good use
of the test results
- Compile the
data from all participants.
- List the problems
that participants had.
- Sort the problems
by priority and frequency of the problem.
- Develop solutions.
Get expert advice if the solutions are not obvious.
- Fix the problems.
- Test the revised
version to ensure you made the right design decisions.
Links
to Related Articles About Usability Testing
A
Usability Test Storyboard, Grant Consulting, http://www.grantconsulting.com/usability_storyboard/index.htm
User
Testing, Jennifer Fleming, http://www.ahref.com/guides/design/199806/0615jef.html
Links
to Related Articles About Using Test Results
Web
Usability: Observed Problems and Solutions, MIT Libraries, http://macfadden.mit.edu:9500/webgroup/usability/
results/solutions.html
How
Usability-Focused Companies Think, User Interface Engineering,
http://world.std.com/~uieweb/focused.htm
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