What eye-tracking methods can reveal about the role of information format in decision-aid processing: an exploratory study.

Abstract

Decision tools can assist patients and families in making informed choices about treatment options. However, information format can influence understanding of treatment options and subsequent treatment decisions, so it is critical to identify formats that support clear and accurate communication. Forty-five older adults made a hypothetical treatment decision about rt-PA therapy for stroke while viewing risk information presented in one of three graph formats (bar, stacked bar, or iconic array). We investigated decisional uncertainty, study time and memory accuracy as a function of graph format. Eye tracking methods explored format-related differences in graph processing. Decisional uncertainty was higher after studying the bar graph, compared to the stacked bar or iconic graph. The bar graph was also associated with poorer memory and longer overall study time. Eye-tracking indicated that graph information was processed in a different order and to a different extent for the three graph types. Understanding how people process information in decision aids is critical for clear communication with decision-makers. Format has been shown to impact information processing, and eye-tracking may be a useful tool to understand these format differences and their implications, and to guide the design of decision aids to optimize communication.