An example of a difference display from HiView 3

A specialist application of the bar chart is the colour-coded ‘difference display’, as used in Hiview 3. A ‘difference display’ shows the magnitude (size) and direction of the difference between two options or treatments. The bars are coded with green and red to indicate whether the first option (Drug A) performs better than the second (Drug D), as selected from the drop-down list at the top of the graph.

The ‘difference display’, in particular, was found to be a very useful visualisation of benefit-risk balance in regulatory decision-making [European Medicines Agency 2012].