Potential communication formats include but are not limited to numeric, graphical (pie, bar, line, pictograph), pictures, illustrations, cartoon, diagrams, icons, visual aids (photographs, animations, computer generated clip art, video clips, pictographs (simple line drawings showing actions to be taken), symbols, and diagrams representing statistical data) symbols and text words. There is ambiguity in the literature surrounding the terms “picture”, “pictograph”, “graph” and “visual aids”.
The literature shows that all non-text communication formats can improve attention, increase understanding and help with information recall, when compared to text alone. It also shows that some formats are better than others. Some formats have increased retention and understanding when they have been used in conjunction with other formats. In addition, some formats have been used more extensively both in practice and in experimental settings than other formats.
Research has shown that:
- Pictures improve attention, comprehension and recall if
- the pictures show relationships among ideas or show spatial relationships (Houts et al. 2006)
- the pictures are closely linked to written or spoken text, as compared to text alone (Houts et al. 2006)
- Patients with low literacy skills are especially likely to benefit from spoken directions plus pictures or from pictures plus very simply worded captions (Houts et al. 2006)
- Using concrete and realistic pictures with clear captions would maximize the benefit of visuals (Mulsow et al.).
In this regard, Houts et al. have reviewed the literature to understand the role of pictures in improving health communication, and based on this review they suggest several design principles (Houts et al. 2006, pp. 188-189):
- Link pictures with text frequently and creatively
- Use the simplest drawings or photographs possible and explain the sequence with simple words. This especially helps viewers with low literacy skills to understand the intended message without being distracted by irrelevant details.
- Simplify the language used with pictures. Pictures will be more easily understood when the accompanying text is clear.
- Give guidance in how to interpret a picture. Captions that describe what is happening in a picture can often be written at a low literacy level
- Be sensitive to the culture of the intended audience (using familiar objects and symbols) in creating or selecting pictures for use in health education materials.
Pictographs
Research has shown that:- Pictographs (compared to text, tables, standard narrative or bar graph) improve attention, comprehension and recall of health information (Chuang et al. 2010; Davis et al. 2010; Hess et al. 2011; Houts et al. 2001; Mulsow et al. ; Price et al. 2007; Schapira et al. 2006; Sorfleet et al. 2009; Tait et al. 2010).
- Horizontal pictographs are perceived faster and more accurately than vertical formats and two-graph pictographs are perceived faster than one-graph formats (Price et al. 2007).
- Textual or spoken information plus pictograph can increase understanding and recall of health information for people with low literacy skills (Hess et al. 2011; Houts et al. 2001; Tait et al. 2010).
- Patients' preferences for, and comprehension of, medical instruction pictographs are age-related (Chuang et al. 2010).
- Shaded pictographs are more effective (Price et al. 2007).
Figure 2: Example of pictograph: “discharge instruction: when you climb stairs (Tetlan 2009)"
Bar Graphs
Research has shown that:- Bar graphs improve comprehension of health information (Davis et al. 2010; Miller and Watkins 2010).
- Vertical bar charts appear to aid understanding (Trevena et al. 2006).
- Bar graphs were preferred to pictorial displays (p < 0.001) when considering breast cancer risk in comparison to heart disease, stroke, and osteoporosis (Schapira et al. 2006).
- Bar graphs plus numerical information largely improve accuracy (Garcia-Retamero and Galesic 2011).
- A bar graph plus a frequency format diagram (compared to a bar graph alone) can improve the short-term accuracy of risk perception among women perceiving inaccurately high risk (Ghosh et al. 2008).
- Parents who read a report with graphs recalled significantly more information correctly than did parents who read a report without graphs (Miller and Watkins 2010).
- 2D graphs (compared to 3D graphs) lead to better comprehension, particularly when complex information is presented. Accuracy is similar for colour and black and white graphs (Stewart et al. 2009).
Other formats
Research has shown that:- Tables (compared to text,) improve comprehension of health information (Tait et al. 2010).
- Children aged 7-11 perform significantly better when probability is presented as a pie chart, in comparison to percentages, proportion notation, proportion-word and mixed format trials. (Ulph et al. 2009).
- Cartoons appear to aid understanding (Delp and Jones 1996; Trevena et al. 2006).
- Visual aids are particularly useful for people with low numeracy but relatively high graphical literacy skills (Garcia-Retamero and Galesic 2011).
- Visual formats result in better understanding than others (Neuner-Jehle et al. 2011)
- Probabilistic information is best represented as event rates (natural frequencies) in relevant groups of people, rather than words (Trevena et al. 2006)
- Icon arrays plus numerical information largely improve accuracy (Garcia-Retamero and Galesic 2011)
- There are significant differences in icon comprehension performance between older and younger mobile phone users (Koutsourelakis and Chorianopoulos 2010).
- There is little evidence to support the effectiveness of information leaflets (Mulsow et al.)
- An enhanced print format tends to be more effective than either a plain format or video (Campbell et al. 2004).
- Patients' inflated perceptions of CHD/stroke risk can be easily corrected using shorter (1-or 5-year) risk communication time frames (Asimakopoulou et al. 2008).