Design, Experimentation.

Design patterns have been claimed to facilitate modification and improve understanding in software design. A controlled experiment was performed to assess the usefulness of portions of a Usability-Supporting Architectural Pattern (USAP) in modifying the design of software architectures to support a specific usability concern. Software engineering and information technology graduate students received different subsets of a USAP supporting cancellation functionality. They then studied a software architecture design and made modifications to add the ability to cancel commands. Results showed that participants who received a usability scenario, a list of general responsibilities, and a sample solution thought of significantly more key issues than participants who saw only the scenario. Implications for software development are that usability concerns can be included at architecture design time, and that USAPs can significantly help software architects to consider responsibilities inherent from usability concerns. Categories and Subject Descriptors H.5.2 [Information Interfaces and Presentations]: Use