Cognitive work analysis and the design of user interfaces

When a user interface needs to be designed for a task that depends on information integration, such as navigation, very few theoretical tools are available. Cognitive task analysis (CTA) and hierarchical task analysis (HTA) are the basic analysis techniques. A choice between them depends on the type of task or objective at hand. In this article, it is argued that for interface design a combination of CTA and HTA forms the basis of the interface definition. When this expanded to a full cognitive work analysis (CWA), it will form the human-factors analysis required for the user-interface design.