Using simultaneous scanpath visualization to investigate the relationship between accuracy and eye movement during medical image interpretation

In this paper, we explore how a number of novel methods for visualizing and analyzing differences in eye-tracking data, including scanpath length, Levenshtein distance, and visual transition frequency, can help to elucidate the methods clinicians use for interpret-ing 12-lead electrocardiograms (ECGs). Visualizing the differences between multiple participants’ scanpaths simultaneously allowed us to answer questions including: do clini-cians fixate randomly on the ECG, or do they apply a systematic approach?; is there a relationship between interpretation accuracy and visual behavior? Results indicate that practitioners have very different visual search strategies. Clinicians who incorrectly inter-pret the image have greater scanpath variability than those who correctly interpret it, indi-cating that differences between practitioners in terms of accuracy are reflected in different eye-movement behaviors. The variation across practitioners is likely to be the result of differential training, clinical role and expertise.