Plan-Do-Check-Act (PDCA)

Something needs to change: Something's wrong, and needs to be fixed, and you've worked hard to create a credible vision of where you want it to be in future. But are you 100% sure that you're right? And are you absolutely certain that your solution will work perfectly, in every way?

Where the consequences of getting things wrong are significant, it often makes sense to run a well-crafted pilot project. That way if the pilot doesn't deliver the results you expected, you get the chance to fix and improve things before you fully commit your reputation and resources.

So how do you make sure that you get this right, not just this time but every time? The solution is to have a process that you follow when you need to make a change or solve a problem; A process that will ensure you plan, test and incorporate feedback before you commit to implementation.

A popular tool for doing just this is the Plan-Do-Check-Act Cycle. This is often referred to as the Deming Cycle or the Deming Wheel after its proponent, W Edwards Deming. It is also sometimes called the Shewhart Cycle.

Deming is best known as a pioneer of the quality management approach and for introducing statistical process control techniques for manufacturing to the Japanese, who used them with great success. He believed that a key source of production quality lay in having clearly defined, repeatable processes. And so the PDCA Cycle as an approach to change and problem solving is very much at the heart of Deming's quality-driven philosophy.

The four phases in the Plan-Do-Check-Act Cycle involve:

Plan: Identifying and analyzing the problem.

Do: Developing and testing a potential solution.

Check: Measuring how effective the test solution was, and analyzing whether it could be improved in any way.

Act: Implementing the improved solution fully.

These are shown in Figure 1 below.

There can be any number of iterations of the "Do" and "Check" phases, as the solution is refined, retested, re-refined and retested again.

How to Use the Tool

The PDCA Cycle encourages you to be methodical in your approach to problem solving and implementing solutions. Follow the steps below every time to ensure you get the highest quality solution possible.

Step 1: Plan

First, identify exactly what your problem is. You may find it useful to use tools like Drill Down, Cause and Effect Diagrams, and the 5 Whys to help you really get to the root of it. Once you've done this, it may be appropriate for you to map the process that is at the root of the problem

Next, draw together any other information you need that will help you start sketching out solutions.

Step 2: Do

This phase involves several activities:

Generate possible solutions.

Select the best of these solutions, perhaps using techniques like Impact Analysis to scrutinize them.

Implement a pilot project on a small scale basis, with a small group, or in a limited geographical area, or using some other trial design appropriate to the nature of your problem, product or initiative.

Our section on Practical Creativity includes several tools that can help you generate ideas and solutions. Our section on Decision Making includes a number of tools that will help you to choose in a scientific and dispassionate way between the various potential solutions you generate.

Note:
The phrase "Plan Do Check Act" or PDCA is easy to remember, but it's important you are quite clear exactly what "Do" means. ""Do" means "Try" or "Test". It does not mean "Implement fully." Full implementation happens in the "Act" phase.

Step 3: Check

In this phase, you measure how effective the pilot solution has been, and gather together any learnings from it that could make it even better.

Depending on the success of the pilot, the number of areas for improvement you have identified, and the scope of the whole initiative, you may decide to repeat the "Do" and "Check" phases, incorporating your additional improvements.

Once you are finally satisfied that the costs would outweigh the benefits of repeating the Do-Check sub-cycle any more, you can move on to the final phase.

Step 4: Act        

Now you implement your solution fully. However, your use of the PDCA Cycle doesn't necessarily stop there. If you are using the PDCA or Deming Wheel as part of a continuous improvement initiative, you need to loop back to the Plan Phase (Step 1), and seek out further areas for improvement.

When to use the Deming Cycle

The Deming Cycle provides a useful, controlled problem solving process. It is particularly effective for:

Helping implement Kaizen or Continuous Improvement approaches, when the cycle is repeated again and again as new areas for improvement are sought and solved.

Identifying new solutions and improvement to processes that are repeated frequently. In this situation, you will benefit from extra improvements built in to the process many times over once it is implemented.

Exploring a range of possible new solutions to problems, and trying them out and improving them in a controlled way before selecting one for full implementation.

Avoiding the large scale wastage of resources that comes with full scale implementation of a mediocre or poor solution.

Clearly, use of a Deming Cycle approach is slower and more measured than a straightforward "gung ho" implementation. In true emergency situations, this means that it may not be appropriate (however, it's easy for people to think that situations are more of an emergency than, in reality, they really are...)

Note:
PDCA is closely related to the Spiral Development Approach which is popular in certain areas of software development, especially where the overall system develops incrementally. Spiral Development repeats loops of the PDCA cycle, as developers identify functionality needed, develop it, test it, implement it, and then go back to identify another sub-system of functionality.

Key Points:

The Plan-Do-Check-Act (PDCA) Cycle provides a simple but effective approach for problem solving and managing change, ensuring that ideas are appropriately tested before committing to full implementation. It can be used in all sorts of environments from new product development through to marketing, or even politics.

It begins with a Planning phase in which the problem is clearly identified and understood. Potential solutions are then generated and tested on a small scale in the "Do" phase, and the outcome of this testing is evaluated during the Check phase. "Do" and "Check" phases can be iterated as many times as is necessary before the full, polished solution is implemented in the "Act" phase.

The How

Here are the basic steps needed for continuous improvement:

This assumes that you have a continuous improvement manager identified (this need not be a full time job for small organizations—this could be as little as 30 minutes a day).

Identify a project that offers a high certainty of visible results — you do not want to have a failure on your first attempt — there will be plenty of time for that in the future as your willingness to take risk grows.

Determine current performance by base lining. Make sure your base line defines the targeted area of improvement.

Obtain commitment of both management and the people in the target area. Define the improvement objective — but in terms of process change not “X” number more widgets. This might be an improvement in quality (scrap/rework reduction), an incremental but undefined reduction in cycle time or ergonomic improvements.

Organize the team. This will include the program manager, the area personnel and supervisor and often members from other areas in the plant as “fresh eyes.” Occasionally, outside help may be beneficial.

Identify the causes of the current performance limitations.

Define potential solutions and test to determine if they will accomplish the improvement objective.

Document an improvement plan that defines exactly how and by whom the changes will be implemented.

Identify and overcome (where possible) unwarranted resistance to the change. There will always be resistance, particularly at the beginning of this journey. Use persuasion whenever possible but be aware that on occasion you may have to move the resistance out of the way.

Implement the change.

Put in place controls to maintain the changes, monitor and verify the results.

Acknowledge and reward the success.  Encouragement of the people, who have made the improvements, however small, is an important component. The success needs to be acknowledged and publicized across the organization with equal credit going to the entire team. Reward the team — but within reason. A pizza party and extended lunch for the team that had a major accomplishment might be far more appropriate in your organization than some flashy award that can cause ill feelings across the entire organization.

Notice the PDCA diagram is a circle — begin again!

I cannot close without a comment on failure — it will happen. Accept that whenever you do something new or different, failure is a possibility. DO NOT go in search of the guilty. Understand why there was a failure, fix the cause, learn from it and move on. If you have followed all the steps the failures will surface during the test phase. Thus the results are only uncomfortable — and possibly embarrassing — not catastrophic.  

Obviously, I cannot do justice to this process in the space limits of this article. There are many excellent books available — one I will recommend is Out of the Crisis by W. Edwards Deming, MIT 1989.

Don’t follow the path — make one — begin the trip and enjoy the journey!

One more Plan-Do-Check-Act (PDCA) Cycle

Also called: PDCA, plan–do–study–act (PDSA) cycle, Deming cycle, Shewhart cycle

The plan–do–check–act cycle (Figure 1) is a four–step model for carrying out change. Just as a circle has no end, the PDCA cycle should be repeated again and again for continuous improvement.

Figure 1: Plan-do-check-act cycle

When to Use Plan–Do–Check–Act

As a model for continuous improvement.

When starting a new improvement project.

When developing a new or improved design of a process, product or service.

When defining a repetitive work process.

When planning data collection and analysis in order to verify and prioritize problems or root causes.

When implementing any change.

Plan–Do–Check–Act Procedure

Plan. Recognize an opportunity and plan a change.

Do. Test the change. Carry out a small-scale study.

Check. Review the test, analyze the results and identify what you’ve learned.

Act. Take action based on what you learned in the study step: If the change did not work, go through the cycle again with a different plan. If you were successful, incorporate what you learned from the test into wider changes. Use what you learned to plan new improvements, beginning the cycle again.

Plan–Do–Check–Act Example (use for case study)

The Pearl River, NY School District, a 2001 recipient of the Malcolm Baldrige National Quality Award, uses the PDCA cycle as a model for defining most of their work processes, from the boardroom to the classroom.

PDCA is the basic structure for the district’s overall strategic planning, needs–analysis, curriculum design and delivery, staff goal-setting and evaluation, provision of student services and support services, and classroom instruction.

Figure 2 shows their “A+ Approach to Classroom Success.” This is a continuous cycle of designing curriculum and delivering classroom instruction. Improvement is not a separate activity: It is built into the work process.

Plan. The A+ Approach begins with a “plan” step called “analyze.” In this step, students’ needs are analyzed by examining a range of data available in Pearl River’s electronic data “warehouse,” from grades to performance on standardized tests. Data can be analyzed for individual students or stratified by grade, gender or any other subgroup. Because PDCA does not specify how to analyze data, a separate data analysis process (Figure 3) is used here as well as in other processes throughout the organization.

Figure 3: Pearl River: analysis process

Do. The A+ Approach continues with two “do” steps:

“Align” asks what national and state standards require and how they will be assessed. Teaching staff also plans curriculum by looking at what is taught at earlier and later grade levels and in other disciplines to assure a clear continuity of instruction throughout the student’s schooling. Teachers develop individual goals to improve their instruction where the “analyze” step showed any gaps.

The second “do” step is, in this example, called “act.” This is where instruction is actually provided, following the curriculum and teaching goals. Within set parameters, teachers vary the delivery of instruction based on each student’s learning rates and styles and varying teaching methods.

Check. The “check” step is called “assess” in this example. Formal and informal assessments take place continually, from daily teacher “dipstick” assessments to every-six-weeks progress reports to annual standardized tests. Teachers also can access comparative data on the electronic database to identify trends. High-need students are monitored by a special child study team.

Throughout the school year, if assessments show students are not learning as expected, mid-course corrections are made such as re-instruction, changing teaching methods and more direct teacher mentoring. Assessment data become input for the next step in the cycle.

Act. In this example the “act” step is called “standardize.” When goals are met, the curriculum design and teaching methods are considered standardized. Teachers share best practices in formal and informal settings. Results from this cycle become input for the “analyze” phase of the next A+ cycle.