PDCA was made popular by W. Edwards Deming, who is considered by many to be the father of modern quality control; however, he always referred to it as the “Shewhart cycle”. Later in Deming’s career, he modified PDCA to “Plan, Do, Study, Act” (PDSA) because he felt that “check” emphasized inspection over analysis. The PDSA cycle was used to create the model of know-how transfer process, and other models.

Along with the other well-known American quality guru-J.M. Juran, Deming went to Japan as part of the occupation forces of the allies after World War II. Deming taught a lot of Quality Improvement methods to the Japanese, including the usage of statistics and the PLAN, DO, STUDY, ACT cycle.

The Deming cycle, or PDSA cycle:

The four successive stages of this cycle stipulate the nature of management’s focus and activities during the review process.

• Plan

First, you need to identify and understand your problem by setting objectives and establishing standards that you want to take advantage of.

• Do

Once you have identified a potential solution, implement plan to achieve objectives and standard with a small-scale pilot project. This will allow you to assess whether your proposed changes achieve the desired outcome, with minimal disruption.

• Check

At this stage, you measure your pilot project’s results against the expectations that you defined in Step 1 to assess whether the idea has worked or not. If it has not worked, you return to Step 1. If it has worked, you go on to Step 4.

• Act

This is where you review your solution against standards and take action. But remember that PDCA is a loop, not a process with a beginning and an end.