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 Basic Methods: 3. Usability testing

 

Methods

– Basic
   1. Stakeholder meeting
   2. Paper prototyping
   3. Usability testing

– Recommended
– Satisfaction questionnaires
– Web site design
– Instructional systems design
– List of methods
– Integration with development

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Purpose

To identify usability problems and obtain measures of usability.

Benefits

  • Major usability problems are identified, including problems related to the specific skills and expectations of the users.
  • Measures can be obtained for the users' effectiveness, efficiency and satisfaction.

Method

Planning

  • Select the most important tasks and user groups to be tested. For educational materials consider testing the teacher interface, the student interface and achievement of learning objectives.
  • Select users who are representative of each user group. 3-5 users are sufficient to identify problems. 8 users of each type are required for reliable measures.
  • Produce a task scenario and input data and write instructions for the user (tell the user what to achieve, not how to do it).
  • Plan sessions allowing time for giving instructions, running the test, answering a questionnaire, and a post-test interview.
  • Invite developers to observe the sessions. If developers cannot be present, videotape the sessions, and show developers edited clips.
  • Two administrators are normally required: one to interact with the user, and one to note problems and to speak to any observers.
  • If possible use one room for testing, linked by video to another room for observation.
  • If usability measures are required, observe the user without making any comments.
  • If measures are not required, prompt the user to explain their interpretation of the contents of each screen and their reason for making choices.

Running sessions

  • Welcome the user, and give the task instructions.
  • Do not give any hints or assistance unless the user is unable to complete the task.
  • Observe the interaction and note any problems encountered.
  • Time each task.
  • At the end of the session, ask the user to complete a [offsite] satisfaction questionnaire such as [offsite] SUMI.
  • Interview the user to confirm they are representative of the intended user group, to gain general opinions, and to ask about specific problems encountered.
  • Assess the results of the task for accuracy and completeness.

Reporting

  • Produce a list of usability problems, categorised by importance (use post-it-notes to sort the problems), and an overview of the types of problems encountered.
  • Arrange a meeting with the project manager and developer to discuss whether and how each problem can be fixed.
  • If measures have been taken, summarise the results of the satisfaction questionnaire, task time and effectiveness (accuracy and completeness) measures.
  • If a full report is required, the [offsite] Common Industry Format provides a good structure.

More information

More information on usability testing can be found in the [offsite] INUSE Handbook.

Alternative methods

Expert evaluation can be used as an alternative, but without user testing there can be no certainty that the product will be usable.

Last updated 11-Jul-00

 

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