PDCA (Plan-Do-Check-Act): Extended Diagram

The Plan-Do-Check-Act (PDCA) cycle also has an extended model which bridges the "Do" and "Check" portions with more detail on how to take action.

In addition to the standard PDCA (Plan-Do-Check-Act) diagram, there is an extended model which expands on the "Do" and "Check" stages. It is a sub-PDCA, and was developed after the original diagram to provide more guidance on how to implement these two steps, which can be ambiguous.

The additional cycle actually uses other tools in the Toyota Way, including the use of visual control (mieruka), 5-whys and Horenso. If you are not yet familiar with these tools, check out the links below for more information.

Main navigation page: Toyota Way Articles
Further reading: Mieruka (visual control), 5-whys, Horenso

Problem Finding

Once you have done something in "Do", you need to discover where the weaknesses and problems are, and what did or did not work. To do so, find out the problems and its root causes using a variety of tools, including 5-why analysis and information gained from reports via Ho-Ren-So.

Further reading: 5-why analysis using a table, Using a fishbone/Ishikawa diagram to perform 5-whys analysis

Display

Once you understand the issues that need to be fixed, you will need to use mieruka (visual control) to visualize the issue. Visualization will make it easier for your team to see where the issue truly lies, which issues to fix in order of priority, and the key indicators of success, or KPIs.

You should make these visualizations physically big, and place them on a wall where it is easy for everyone to see. Common visualizations include Gantt charts, wall charts which displays the issues in order of priority and even the display of the Fishbone/Ishikawa diagram made during the five-whys analysis in the Problem Finding stage.

Clear

Find solutions to the issues you have identified. In doing so, keep updating your visual control displays to ensure everyone stays in-the-loop, and can easily see the project status.

Acknowledge

At this stage, you should understand and acknowledge the problems and solutions. From here, communicate to your team as well as all stakeholders as to your analysis, conclusions, and actions to take.

Moving forward

From here you would go back into the regular PDCA cycle onto "Act", in which you would implement the actions planned.