Design issues of the existing radiotherapy segmentation software

Findings from previous literatures, ethnography studies and interviews showed that radiotherapy contouring interfaces are very complex, requiring many human-computer interactions (HCI). In this paper we used observational, heuristic evaluation, think aloud and NASA-TLX methods to 1) analyse the workflow of radiotherapy segmentation systems; 2) discover possible usability and HCI design issues of current segmentation systems in order to identify the requirements for future interface design; and 3) explore the abilities and limitations of various evaluation methods. From the results it can be seen that observational and think aloud methods were very useful in identifying the workflow of different systems. The heuristic evaluation method uncovered more general usability issues with the interface design. The think aloud method identified more HCI issues compared to general usability issues. From the NASA-TLX, it can be seen that the workload level of system C is higher in almost all the categories. Using the four different methods this study identified several usability and HCI issues and have proposed seven main requirements which might be considered in our future studies.