Subjective Usability Evaluation: A Comparison of Four Methods
Ian Wesley Robertson · Rice Research Repository (Rice University) · 2018
Subjective usability assessments play a key role in usability research. Several divergent methods of collecting subjective data have developed within usability research literature. This study compared four methods of collective subjective usability data with the System Usability Scale (SUS). Users were asked to use and rate three products with the SUS: a library website, an electric can opener, and a digital timer. Use-Then-Measure, a name applied to usability testing, was used as a reference group to compare the performance of the other three methods. Retrospective usability assessment proved the most promising of those three methods as it generated mean SUS scores that were not statistically distinguishable from the Use-Then-Measure condition. Both the Prospective, judging before use, and Watching-Others, rating products based on video footage, conditions generated mean SUS scores higher than Use-Than-Measure. Retrospective assessment has the most support as an alternative method to usability testing for collecting subjective usability scores. More research is needed to understand if Watching-Others and Prospective methods can be utilized effectively.