TRUMP Cost-effective User Centred Design

Recommended methods: 8. Evaluate Prototype


To obtain rapid feedback on the usability of prototypes.


Potential usability problems can be detected at an early stage before development is complete.


A simplified version of usability testing is used. Only 3-5 users are required, and it is usually best to prompt the user to explain their interpretation of the contents of each screen and their reason for making choices. However, if estimates of usability measures are required, ask the user to think aloud, but do not interrupt them.


  • 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.

Alternative methods

If the necessary skills are available, the design can be evaluated and improved by expert evaluation. This can complement prototyping, or use methods which replace users by usability experts if it is impossible to gain access to users.

Next steps

Once a complete system is available, use usability testing to ensure that all requirements have been met.

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