A histogram is a bar graph of the frequency distribution of measurements. The information can be collected in the form of a checklist initially and then displayed in the form of a Histogram that will effectively highlight the interval that is most frequently occurring.

An example would be to line up by height a group of people in a course. Normally one would be the tallest and one would be the shortest and there would be a cluster of people around an average height. Hence the phrase “normal distribution”.

This tool helps identify the cause of problems in a process by the shape of the distribution as well as the width of the distribution.

Figure 1: Example Histogram
Histogram Example

To learn more about Histograms please refer to the Institute for Healthcare Improvement website. You may need to take a moment and register with the IHI for more in-depth information.


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