Using Eye Tracking to Assess the Navigation Efficacy of a Medical Proxy Decision Tool.

Making a life-or-death decision about the best course of action for a loved one is emotionally taxing and cognitively complex. Decision aids can help reduced the burden by providing relevant important information that facilitates decision making while allowing the decision maker to process the information at their own pace. Given the intense cognitive effort required to process complex medical alternatives, it is crucial to provide a decision aid that is easy to understand and easy to use. We designed a digital decision aid based on a validated paper-based decision aid targeting proxies making survival or comfort care decisions for their loved ones suffering traumatic brain injury. In this study, we focused on the effects of navigation design, which plays an essential role in helping users consume the provided content. We used eye tracking to study users’ information processing and navigation behavior throughout the entire decision making process. Our results showed that one of our navigation designs reduced the feeling of “lostness” and improved the overall perception of the usability of the tool. The same navigation design improved the information processing behavior by increasing engagement with the system and helped decision makers spend more time processing content rather than searching for the provided information.