Development and Evaluation of a Model-based Usability Assessment Tool for Interactive CAS-Systems

摘要

Technological progress in the field of Computer-Assisted Surgery (CAS) not only leads to an enhancement in efficiency and effectiveness concerning therapeutic results but also to a change of the Human-Computer-Interaction characteristics in the operating room (OR). Deficiencies in the use process of CAS systems bring along high potential for hazardous human-induced failures implicating higher risk for patients and physicians during surgical interventions. To enhance safety and reliability in modern surgical work systems the design of the user interfaces has to be not only “ergonomic” -usability and reliability are major characteristics to be taken into consideration for the approval as well as for routine application of medical devices. While experimental and criteria-oriented usability-evaluation of interactive systems are receiving increasing attention from manufacturers of medical devices, the design engineer has to examine and determine the usability of an envisioned system already in a very early developmental phase. In this context the presented mAIXuse method as well as a corresponding software tool have been developed and are currently being evaluated in order to support the application of prospective usability assessment for complex medical devices. Adapted from two model-based methods, the Concur Task Tree methodology and the CPM-GOMS approach, the software tool uses formal, normative models to predict user and system behaviour in order to estimate the usability of a new or re-designed system. The developed prospective usability investigation approach has already been evaluated in comparison to conventional risk assessment and usability evaluation methods and the corresponding software tool has been evaluated in cooperation with medical and industrial partners. The aim of the presented work is to support especially small and medium sized enterprises developing and manufacturing medical devices, taking into account the required usability engineering and risk management process.