On the dimensionality of the System Usability Scale: A test of alternative measurement models

Simone Borsci*, Stefano Federici, Marco Lauriola

*Corresponding author for this work

    Research output: Contribution to journalArticleAcademicpeer-review

    108 Citations (Scopus)

    Abstract

    The System Usability Scale (SUS), developed by Brooke (Usability evaluation in industry, Taylor & Francis, London, pp 189-194, 1996), had a great success among usability practitioners since it is a quick and easy to use measure for collecting users' usability evaluation of a system. Recently, Lewis and Sauro (Proceedings of the human computer interaction international conference (HCII 2009), San Diego CA, USA, 2009) have proposed a two-factor structure-Usability (8 items) and Learnability (2 items)-suggesting that practitioners might take advantage of these new factors to extract additional information from SUS data. In order to verify the dimensionality in the SUS' two-component structure, we estimated the parameters and tested with a structural equation model the SUS structure on a sample of 196 university users. Our data indicated that both the unidimensional model and the two-factor model with uncorrelated factors proposed by Lewis and Sauro (Proceedings of the human computer interaction international conference (HCII 2009), San Diego CA, USA, 2009) had a not satisfactory fit to the data. We thus released the hypothesis that Usability and Learnability are independent components of SUS ratings and tested a less restrictive model with correlated factors. This model not only yielded a good fit to the data, but it was also significantly more appropriate to represent the structure of SUS ratings.

    Original languageEnglish
    Pages (from-to)193-197
    Number of pages5
    JournalCognitive processing
    Volume10
    Issue number3
    DOIs
    Publication statusPublished - 1 Aug 2009

    Keywords

    • Questionnaire
    • System Usability Scale
    • Usability evaluation

    Fingerprint Dive into the research topics of 'On the dimensionality of the System Usability Scale: A test of alternative measurement models'. Together they form a unique fingerprint.

  • Cite this