A run chart is a graph that displays observed data in a time sequence1. It is often used to visualize trends or patterns over time1. In the context of healthcare quality, a run chart would be the most suitable tool to display nosocomial infection rates over time1. This is because it allows for the tracking of changes in the data over time, which can help in identifying any trends or shifts in the process1. This can be particularly useful in monitoring infection rates, as it can help in identifying periodsof increase or decrease, which can then be investigated further1.