PDCA (plan-do-check-act)

PDCA (plan-do-check-act, sometimes seen as plan-do-check-adjust) is a repetitive four-stage model for continuous improvement (CI) in business process management. 

The PDCA model is also known as the Deming circle/cycle/wheel, Shewhart cycle, control circle/cycle, or plan–do–study–act (PDSA). 

The model is implemented to improve the quality and effectiveness of processes within product lifecycle management, project management, human resource management (HRM), supply chain management (SCM) and many other areas of business. 

PDCA was popularized by Dr. W. Edwards Deming, an American engineer, statistician and management consultant. Deming is often considered the father of modern quality control (QC). 

Deming's theories form the basis for TQM (Total Quality Manangement) and ISO 9001 quality standards. Demings himself credited Walter Andrew Shewhart as the creator of the cycle, however. Shewhart was an American physicist, engineer and statistician who is often considered the father of statistical quality control.

TQM processes are often divided into the four sequential categories: plan, do, check, and act.

Here's an example of how PDCA is broken down in TQM :

Plan: Define the problem to be addressed, collect relevant data, and ascertain the problem's root cause.

Do: Develop and implement a solution; decide upon a measurement to gauge its effectiveness.

Check: Confirm the results through before-and-after data comparison.

Act: Document the results, inform others about process changes, and make recommendations for the problem to be addressed in the next PDCA cycle.