Pie charts of hazardous waste risks

Reproduced from Lipkus, I.M. & Hollands, J.G. 1999. The visual communication of risk. Journal of the National Cancer Institute Monographs, 25, 149-163.

The picture above shows a series of probabilities of each hazardous waste risk as a part on separate pie charts. The pie chart showing joint probabilities (bottom rightmost) summarises the information into a single pie chart and may be more effective than presenting separate information on two pie charts. Without the printed numerical values in pie charts above, it is very difficult to rank the slices in pie charts since most of the sizes are similar. It is also difficult to compare slices between pie charts. When relying on printed values to make sense of a chart, a table would have been a better alternative (see Few 2006).