PDCA

Continuous Improvement

Another cornerstone of the Workplace Challenge’s User Group programme is the PDCA cycle.

Continuous improvement is not possible without continuous planning, doing (implementing plans), checking (to see if the result is according to plan) and taking action, if the results are not forthcoming.

The acronym PDCA originated in the “Scientific Method”, as developed by Walter A Shewhart from the work of Francis Bacon (Novum Organum, 1620). The scientific method can be written as “hypothesis” - “experiment” - “evaluation” or Plan, Do, and Check. Shewhart described manufacture under “control” - under statistical control - as a three step process of specification, production, and inspection. He also specifically related this to the Scientific Method of hypothesis, experiment and evaluation. Shewhart says that the statistician “must help to change the demand [for goods] by showing…how to close up the tolerance range and to improve the quality of goods.” Clearly, Shewhart intended the analyst to take action based on the conclusions of the evaluation.

This cycle is therefore called the Shewhart cycle:

PLAN

Establish the objectives and processes necessary to deliver results in accordance with the specifications.

DO

Implement the processes.

CHECK

Monitor and evaluate the processes and results against objectives and Specifications and report the outcome.

ACT

Apply actions to the outcome for necessary improvement. This means reviewing all steps (Plan, Do, Check, Act)
and modifying the process to improve it before its next implementation.

PDCA was made popular by Dr. W. Edwards Deming, who is considered by many to be the father of modern quality control; however it was always referred to by him as the “Shewhart cycle.” Later in Deming’s career, he modified PDCA to “Plan, Do, Study, Act” (PDSA) so as to better describe his recommendations. According to Deming during his lectures in Japan in the early 1950’s the Japanese participants shortened the steps to the now traditional Plan, Do, Check, Act. Deming preferred Plan, Do, Study, Act because ‘Study’ has connotations in English closer to Shewhart’s intent than “Check.” In recognition of this perhaps we should make all references to PDSA, not PDCA. A fundamental principle of the scientific method and PDSA, is iteration - once an hypothesis is confirmed (or negated), executing the cycle again will extend the knowledge further. Repeating the PDSA cycle can bring us closer to the goal, usually a perfect operation and output. In Six Sigma programs, the PDCA cycle is called “Define, Measure, Analyze, Improve, Control” (DMAIC). The iterative nature of the cycle must be explicitly added to the DMAIC procedure.

The importance of PDCA can be seen in every mini-business of the WPC User Group or Cluster companies – there is usually a poster reminding team members to Plan, Do, Check and Act. Good results should also be celebrated!