In this study, a decision support system (DSS) for usability assessment and design of web-based information
systems (WIS) is proposed. It employs three machine learning methods (support vector machines,
neural networks, and decision trees) and a statistical technique (multiple linear regression) to reveal
the underlying relationships between the overall WIS usability and its determinative factors. A sensitivity
analysis on the predictive models is performed and a new metric, criticality index, is devised to identify
the importance ranking of the determinative factors. Checklist items with the highest and the lowest contribution
to the usability performance of the WIS are specified by means of the criticality index.