Cognitive Task Analysis for prospective usability evaluation in Computer-Assisted Surgery

Within the framework of the INNORISK (Innovative Risk Analysis Methods for Medical Devices) project, a twofold strategy is pursued for prospective usability assessment of Computer-Assisted Surgery (CAS) systems in the context of a risk management process. In one approach ConcurTaskTrees are applied to accomplish a hierarchical task analysis including temporal relations. In the other approach, based on the Cognitive Task Analysis method CPM-GOMS (Cognitive Perceptual Motor-Goals Operators Methods Selection Rules), a new technique for detecting potential contradictions and conflicts in the use of concurrent cognitive resources is generated. Within this model-based approach, extrinsic and intrinsic performance shaping factors are comprised, taking into account the specific context of modem surgical work systems. Additionally, a computer assisted usability analysis tool including the above-mentioned methods is developed to provide support for small and medium-sized enterprises in early stages of the design development process of risk sensitive Human-Machine-Interfaces in medical systems.