Comparison of four visual analytics techniques for the visualization of adverse drug event rates in clinical trials

Abstract

Drugs are evaluated and compared during clinical trials, and the observed adverse drug events are recorded. Many trial results are available online in trial registries, such as ClinicalTrials.gov. However, this data remains little used currently, due to the volume and the tabular presentation.In this paper, we focus on the visualization of adverse drug event rates, aggregated in 13 anatomical categories and 2 levels of seriousness. We designed four interactive visual analytics: horizontal stacked bar chart with labels, vertical stacked bar chart, area-proportional flower glyphs and star glyphs. We compare the four approaches, analytically and through a preliminary user study aimed at determining the user preferred visual analytics, and we identify their advantages and disadvantages. We conclude that the best options are the horizontal stacked bar chart, which allows labels to help identify the categories of adverse drug events, and the area-proportional flower glyph, which permits a better visualization of small values when very high values are present.