Prospects and Pitfalls in Combining Eye-Tracking Data and Verbal Reports

It is intuitively appealing to try to combine eye-tracking data and verbal reports when investigating medical image interpretation. However, before collecting such data, important decisions must be made, including exactly when and how to collect the verbal reports. The purpose of this methodological article is to reflect on the pros and cons of different solutions and to offer some guidelines to investigators. We start by exploring the ontology of vision and speech production and the epistemology of eye movements to grasp what fixations and verbal reports actually reflect. We are also interested in the major constraints of the two systems. Second, we elaborate on two dominant investigational approaches to verbal accounts: concurrent think-aloud and Chi's explanations. Later, we move on to other approaches. Third, we present and critically evaluate studies from the literature on medical image interpretation, specifically ones that have sought to contrast or integrate eye-movement data and verbal reports. Fourth, we conclude with some practical guidelines and suggestions for further research.