University of Western Ontario - Electronic Thesis and Dissertation Repository


Doctor of Philosophy


Electrical and Computer Engineering


Dr. Luiz Fernando Capretz


User satisfaction has always been a major factor in the success of software, regardless of whether the software is closed proprietary or open source software (OSS). Although user-centered designs are gaining recognition among the OSS community, many design scenarios still do not incorporate usability as one of their primary goals. Accordingly, many individuals believe that if OSS was more usable, its popularity would increase tremendously. Although there are strong examples of usable open source software, there is still potential to improve the usability of OSS. The usability assessment of open source projects is an area where relatively little research has been conducted, and, accordingly, the main contribution of this work is a methodology that evaluates the usability maturity of an OSS project. Consequently, we present a usability maturity model that is aimed at usability-related issues for open source projects. The model has been developed in response to a need for measuring the extent to which open source software projects support usability. Specifically, it is intended for assessing and improving the usability aspect in open source software development. The proposed model examines the relationship between open source projects and their usability aspects. The measuring instrument for the model contains factors that have been selected from four of our empirical studies, which examine the perspectives of OSS users, developers, contributors and the industry. In addition to presenting the usability maturity model, this thesis discusses assessment questionnaires, a rating methodology and two case studies.