The engineering practices applied in usability assurance are procedures used in the design and development of interactive systems.
Practices of usability assurance
Usability assurance is conducted throughout the development cycle, by iterating interaction design, validation and feedback:
- At the design stage, it is based on methodologies and practices for:
- Anticipating how users may behave when using the product or the service (as opposed to assessment of how users should behave, according to the opinion of the product and service developer).
- Designing the user interface to ensure seamless interaction with the product. An example of a methodology for usability assurance by design is presented in Dustin et al. (2001).
- At the validation stage, it consists of methodologies and practices for verifying that the users behave as intended and that the user interface responds gracefully in cases of deviations from the designers’ intention. An example of a book presenting common testing practices is the one by Duma and Redish (1999).
Common practices for usability validation include virtual testing based on models of the interaction, and testing with users (notably, opinion questionnaires, usability testing) and activity analysis.
- Common practices for getting feedback include off-line and integrated feedback questionnaires and on-going activity control.
-  Harel, Kenett and Ruggeri, Modeling web usability diagnostics on the basis of usage statistics
- Dustin, E., Rashka, J., and McDiarmid, D., (2001). Quality Web Systems: Performance, Security, and Usability. Addison-Wesley, Reading, MA.
- Duma, J.S. and Redish, J.C. (1999). A Practical Guide to Usability Testing. Intellect Ltd, Bristol, UK.