Linking UI design to training effectiveness, efficiency, and satisfaction in central venous catheterization simulation

The purpose of this study is to understand what updates to the user interface (UI) of our medical training simulator, the DHRT+, led to an increase in usability as defined by its three pillars—effectiveness, efficiency, and satisfaction. Medical error is a leading cause of death in the United States. Central venous catheterization (CVC) is a large contributor to this issue with its 15 % complication rate, which is primarily linked to the experience of the physician. Current training methods for CVC are limited by inadequate practice time, the inability for full procedural practice, and the lack of anatomical variety and feedback. To combat these issues, the Dynamic Haptic Robotic Trainer (DHRT+) was developed as a new training alternative. Our investigation included statistical analysis of the changes in first-year medical residents’ usability of the DHRT+ training. Additional analysis was conducted using a Mask R-CNN algorithm to map gaze fixations on targeted areas of UI improvement. Comparing performances from training bootcamps in 2023 and 2024, findings revealed mixed outcomes: a marginal improvement in perceived usability (SUS), a trend toward faster VOP completion times, and significant changes in gaze behavior reflecting altered user strategies. Effectiveness metrics (failure count and tip-tracking rate) did not show significant improvement. Qualitative feedback highlighted that clearer instructions and real-time feedback were viewed as the most beneficial UI updates. The work of this study contributes to the broader impact of providing a framework for essential UI changes for improving the usability of simulations in healthcare. These results demonstrate how usability principles, such as on-the-spot feedback, improved instructional quality, and intuitive UIs can be used to improve training results and promote patient safety.