Search the internet for “What is SPC?” and there are many definitions and descriptions of statistical process control that are correct but not complete. They are true but not the whole truth.

From the search results, a general definition and description of SPC could be as follows.

Definition: SPC is the application of statistical tools and techniques to find, analyze, and control variation in processes.

Description: Find. Monitor, measure, and collect data using tools such as control charts for variables data(i.e., average/range charts, average/standard deviation charts, run tests, etc.) and control charts for attributes data (i.e., c charts, p charts, u charts, etc.) Analyze. Through descriptive analysis of data and charts (using histograms, Pareto charts, scatter plots, etc.) Control. Employ techniques for problem solving (brainstorming, critical thinking, using fishbone diagram, flowcharts, etc.) and for process capability (capability ratio—Cr, performance ratio—Pr, capability index—Cp, process capability—CpK, etc.)

With so many ways of obtaining data and attaining knowledge, how could this description not be complete answer to “What is SPC?”

The description falls short in explaining what to do with the attained knowledge. How do you apply and develop the knowledge beyond its usefulness in monitoring processes for corrective actions or maintaining status quo.

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