Pictographs and icon arrays are two names for a type of risk communication graphic that CBSSM investigators have developed and extensively tested. Because pictographs are made up of a matrix of unique elements representing individual units (people) within the at-risk population, they accurately communicate exact percentages while simultaneously conveying “gist” impressions derived from the relative proportion of colored vs. uncolored area in the graph. Click here to learn more and create your own downloadable pictograph images.
Pictographs combine some of the best elements of alternate communication formats such as tables or bar charts. A pictograph is made up of unique icons 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 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). Another study (2010) showed that simpler pictographs (ones that showed a single risk) appeared to be more effective than more visually complex pictographs that used multiple colors to show different risks simultaneously. In a similar vein, two studies (2011, 2012) have found advantages of using static pictographs instead of more complex animated or interactive versions (perhaps because these elements distract attention from the part-whole relationship that represents the risk being communicated).
CBSSM researchers are not alone in our use of pictographs. Other researchers have shown that image matricies 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). More recent work has shown that icon arrays overcome some of the barriers to comprehension caused by low numeracy (e.g., Galesic & Garcia-Retamero, 2009 & 2010; Garcia-Retamero & Galesic, 2009). In fact, it appears that high numeracy and low numeracy people use pictographs in different ways (Hess, et al, 2011).
To encourage broader use of pictographs in risk communication and medical decision-making in general, CBSSM has collaborated with the UM Risk Center to develop Iconarray.com, a web-based application that enables people to develop and download their own tailored icon array graphics. A companion site, clinician.iconarray.com, enables clinicians (or anyone else) to make side-by-side icon array displays for use in consultations in less than 1 minute.