Usability measurement in context

Different approaches to the measurement of usability are reviewed and related to definitions of usability in international standards. It is concluded that reliable measures of overall usability can only be obtained by assessing the effectiveness, efficiency and satisfaction with which representative users carry out representative tasks in representative environments. This requires a detailed understanding of the context of use of a product. The ESPRIT MUSiC project has developed tools which can be used to measure usability in the laboratory and the field. An overview is given of the methods and tools for measuring user performance, cognitive workload and user perceived quality. Contents 1. Benefits of improved usability............................................................................................................................ 1 1.1. Usability evaluation and system development................................................................................ 1 2. Usability features and attributes....................................................................................................................... 2 2.1. Can usability be measured in terms of features and attributes?................................................... 2