USABILITY TESTING ON A BUDGET - A NASA USABILITY TEST-CASE STUDY

Okay, so you've purchased a graphical user interface (GUI) builder tool to help you quickly build a sophisticated user interface, and your developers promise to follow a particular style guide (e.g., OSF/Motif, Apple/Macintosh) when creating the GUI. This is definitely a step in the right direction, but it is no guarantee that the application's user interface will be usable; that is, where the user interface helps, rather than hinders, the end-users from doing their jobs. Numerous techniques for testing the usability and user satisfaction of an application's GUI are available, such as design walk-throughs, field testing with beta releases, demonstrations of prototypes to future end-users, and user questionnaires. One of the most effective techniques is usability testing with defined tasks and metrics, and yet, it is not commonly used in project development life cycles at the National Aeronautics and Space Agency (NASA). This paper discusses a low-budget, but effective, approach we used at NASA's Goddard Space Flight Center (GSFC) to perform structured usability testing. It did not require any additional staff or a usability laboratory, but did successfully identify problems with the application's user interface. The purpose of the usability testing was two-fold: (1) to test the process used in the usability test; and (2) to apply the results of the test to improving the subject software's user interface. This paper will discuss the results from the test and the lessons learned. It will conclude with a discussion of future plans to conduct cost benefit analysis and integrate usability testing as a required step in a project's development life cycle.