Which statistical tool is used for quality control to monitor process variation?

The control chart is a vital statistical tool used for quality control, focusing specifically on monitoring process variation over time. It provides a visual representation that helps identify trends, patterns, and outliers in data related to a production process. By plotting individual measurements or averages against predetermined control limits, it allows teams to discern whether a process is stable and in control or if there are indications of variations that could signify issues that need addressing.

Control charts facilitate the detection of variations that may arise from common causes (inherent to the process) or special causes (external factors), enabling organizations to maintain consistent quality. This capability makes control charts essential for continuous improvement initiatives, helping organizations to achieve desired quality standards and optimize efficiency.

In contrast, histograms are used to display the distribution of data, Pareto charts prioritize problems based on their frequency or impact, and scatter diagrams illustrate relationships between two variables. While all these tools play a role in quality management, they do not specifically focus on monitoring process variation in the same continuous and dynamic way as control charts do.