Demingcyclus

Demingcyclus, or the PDCA cycle, is a simple, iterative management method used to achieve continuous improvement in processes and products. The cycle’s name derives from its four phases: Plan, Do, Check, and Act. It is widely attributed to W. Edwards Deming, although its origins lie in the work of Walter A. Shewhart, who proposed a similar cycle for quality control. After World War II, Deming popularized the approach in Japan, where it became a foundational element of modern quality management and continuous improvement practices, later spreading to manufacturing, services, and public sector organizations.

In operation, the Demingcyclus begins with planning: identifying a problem or opportunity, establishing objectives, and designing a change or experiment. In the Do phase, the change is implemented on a small scale or in a controlled pilot. In the Check or Study phase, data are collected and analyzed to determine whether the change produced the desired effect. In the Act phase, a decision is made to adopt, modify, or abandon the change, and the cycle then begins again with a new plan, incorporating what was learned.

Variations include plan-do-study-act (PDSA), often used in healthcare to emphasize learning, and plan-do-check-act, which stresses verification. The Demingcyclus emphasizes data-driven decision-making, standardization, and the gradual buildup of knowledge through repeated testing. It is a core component of many quality management frameworks, including total quality management and lean manufacturing.