Description:
<jats:p> Because an increasing number of systems are being developed to support complex cognitive functioning, task analysis is commonly being augmented with cognitive task analysis, which identifies cognitive processes, knowledge, and mental models relevant to task performance. Cognitive task analysis tends to be lengthy and time-consuming, so designers frequently ask how they might know if it is actually necessary for a specific project. In this paper, we assume that much of the need for cognitive task analysis depends on the inherent “cognitive complexity” of the task. We present a model of cognitive complexity, and show how it was used to develop a computer-based tool for estimating relative cognitive complexity for a set of tasks. The tool, Cog-C, elicits task and subtask hierarchies, then guides the user in making relatively simple estimates on a number of scales. The tool calculates and displays the relative cognitive complexity scores for each task, along with subscores of cognitive complexity for different types of knowledge. Usability and reliability were evaluated in multiple domains, showing that the tool is relatively easy to use, reliable, and well-accepted. </jats:p>