What is Usability Testing?
When is Usability Testing appropriate?
Usability testing is not a substitute for a human-centred design process.
Who should attend?
• A representative user
• A test host.
• At least 1 business representative.
Observers should ideally be in a separate
How many test sessions should be conducted?
This depends on the complexity of the system, the number of intended users, and budgetary constraints. Even one test session is better than
none, but 6 to 8 will tend to uncover the majority of significant issues.
How to prepare for Usability testing:
• Identify representative tasks. Ideally, these should derive from scenarios or use cases developed earlier in the design process. Have a clear definition of when a task is complete.
• Prepare a test schedule.
• Book the required room/s.
• Identify representative users and invite them to attend.
We will need the following materials:
• A consent form for video-taping (if conducted).
• A pre-evaluation questionnaire to check that your participants match the required profile, and to check whether any effects observed are dependent on demographic attributes.
• A list of tasks, together with criteria for measuring whether they have been successfully completed.
• Logging sheets to record timing, events, participant actions, concerns and comments.
• A post-evaluation questionnaire to measure user satisfaction and understanding and to glean any additional information participants
may want to provide.
• Cash or an appropriate ‘thank-you’ gift.
• Ensure participants are put at ease, and are fully informed of any taping or observation. Attend at least one test as a participant, to
appreciate the stress that participants undergo.
• Ensure that participants have the option to abandon any tasks which they are unable to complete.
• Do not prompt participants unless it is clearly necessary to do so.
• Record events in as much detail as possible— to the level of keystrokes and mouse clicks if necessary.
• If there are observers, ensure that they do not interrupt in any way. Brief observers formally prior to the test.
• Be sensitive to the fact that developers may be upset by what they observe or what you report.
Goals of usability testing
Usability testing is a black-box testing technique. The aim is to observe people using the product to discover errors and areas of improvement. Usability testing generally involves measuring how well test subjects respond in four areas: efficiency, accuracy, recall, and emotional response. The results of the first test can be treated as a baseline or control measurement; all subsequent tests can then be compared to the baseline to indicate improvement.
Performance: How much time, and how many steps, are required for people to complete basic tasks? (For example, find something to buy, create a new account, and order the item.)
Accuracy: How many mistakes did people make? (And were they fatal or recoverable with the right information?)
Recall: How much does the person remember afterwards or after periods of non-use?
Stickiness: How much time he/she spends
Emotional response: How does the person feel about the tasks completed? Is the person confident, stressed? Would the user recommend this system to a friend?
To assess the usability of the system under usability testing, quantitative and/or qualitative Usability goals (also called usability requirements have to be defined beforehand. If the results of the usability testing meet the Usability goals, the system can be considered as usable for the end-users whose representatives have tested it.