Pictographs / Icon Arrays

A main research focus at CBSSM is risk communication and, in particular, the use of visual graphics to display risk information. One format that we have found to particularly useful is the pictograph or icon array, which is a matrix of elements that are shaded different colors to represent the proportion of a given population that may experience a condition, disease, or treatment complication.

About Pictographs

Pictographs combine some of the best elements of alternate communication formats such as tables or bar charts. A pictograph is made up of unique elements representing individual units (people) within the at risk population. As a result, it accurately communicates exact percentages the way a table does. However, pictographs also convey "gist" impressions derived from the relative proportion of colored vs. uncolored area in the graph. As such, they are similar in effectiveness to bar graphs and other area or height-based graphics. Furthermore, pictographs are like pie charts in that they represent the entire risk denominator visually, unlike bar charts which focus attention primarily on the risk numerator.

CBSSM researchers Angie Fagerlin, Brian Zikmund-Fisher, and Peter Ubel, have shown that using pictographs in risk communication contexts can be used to effectively communicate the incremental benefit of risk reducing treatments (Zikmund-Fisher, 2008) and the risk of developing side effects from medications, especially when multiple colors are used to distinguish the incremental risk caused by treatment (Zikmund-Fisher, 2008)). Pictographs can also limit the biases induced by the presence of powerful anecdotal narratives of former patients (Fagerlin, 2005) and incremental risk formats (Zikmund-Fisher, 2008). In a study that directly compared graphical formats, pictographs were also the only graphical format that supported acquisition of both verbatim and all-important "gist" knowledge (Hawley, 2008). A sample incremental risk graphic from one of our studies is shown below.

CBSSM researchers are not alone in our use of pictographs. Other researchers have shown that image matrices of this type are easier to interpret quickly and accurately than other formats (Feldman-Stewart, 2007), are sometimes preferred by patients (Schapira, 2006), and may reduce side effect aversion in treatment decision making. (Waters, 2007)

To encourage broader use of pictographs in risk communication and medical decision making in general, CBSSM is making available our "picto-generator" web-based application. We only request that attribution to the CBSSM pictograph generator application (please use http://tools.cbssm.org) is made if an image created by this application is used in clinical or research applications and any associated publications.

Click here to see the many possible types of pictographs and to create your own images.