8D - DMAIC - 5 WHY  Problem Solving
Resource Center

A question that I get from time to time is "What's the difference between the problem solving methods of 8D, DMAIC and 5 Why?". Then the follow-up question is "Which one should we use?" or "Which one do you think we should use?".

I can easily answer the first question about what the are the differences. The follow-up questions about which to use is difficult to answer. Each of the problem solving methods is designed to find the root cause of the problem and then to develop a lasting solution or countermeasure.

Which one to use depends on several factors:

• Do your customers have a preference?
• How skilled are your employees in team dynamics?
• What is the culture in your organization? Laid back, formal, quality driven, etc. 
• How much time and resources can be used for structured problem solving?
• Is the organization discplined in collecting, analyzing and distributing quality related data?
• Can you develop and deploy the required training to learn structured problem solving?, and
• a dozen more questions that might come to mind.

Similarities of the methods

First let's look at the common ingredients of the three methods. All are step-by-step problem solving methods. The 8D and DMAIC methods rely on a data collection, analysis, and using problem solving tools such as brainstorming, cause and effect diagrams (fishbone), etc. The 5 Why method being the least formal may be performed strictly on the information that is at hand.

For that reason the 5 Why method can easily get "off track" and the root cause missed. In order to avoid that possibility we have added another step to the 5 Why method to keep the team on track. Read more about our 5 Why training.

The 8D problem solving method uses eight steps. Whoa there Captain Obvious! Each step is called a discipline, hence 8D. The DMAIC problem solving method has five steps. Let's take a look at the steps in each method:

The 8D Problem Solving Method

1. Use a team approach
2. Describe the problem
3. Implement Interim Action
4. Defining Root Cause
5. Verifying Corrective Action
6. Implementing Permanent Actions
7. Prevent Recurrence
8. Congratulate The Team

The DMAIC Method

1. Define - define the problem
2. M - determine the key process measurements
3. A - analyze the the measurement data
4. I - improve the process
5. C - control the new

The DMAIC problem solving method is commonly used with Six Sigma process improvement projects. While the 8D method was developed and used primarily in the automotive industry. However, because it is extremely efffective in finding root causes and providing long-term solutions, it is now used in nearly every type of organization.

Which one do I use?

I use all three depending on the type of problem and the situation involved. When working with an organization on long-term improvement projects using a six sigma methodology or lean six sigma my preference is DMAIC.

If I'm helping a company with problem solving external of a formal improvement project then 8D is my choice. It is universal in approach whether the problem is product or service related. I especially like the third (interim action) and eighth (congratulate the team) steps that are not included in the other methods.

The interim action step is intended to stop the hemoraging of defects getting to the customer and the team recognition is vital to maintain interest in spending time on real problem solving.

The 5 Why problem solving method is a good choice for the "down and dirty, in a hurry" folks. If caution is applied and the correct questions are ask it can be very effective.

Where to go from here.

All of the methods can produce significant process improvement by removing the root causes.

• All of them are better than the "shoot from the hip" problem solving that never produces long-term improvement.
• Pick one and stick with it until it becomes comfortable.
• Concentrate on data collection, analysis and preventing recurrence.
• Use the same method every where in the organization so all employees are familiar with the approach, tools and terminology.
• You can try changing the order of some of the steps to better fit a situation or organization. However, do not eliminate any of the steps.

The 8D and DMAIC methods rely on similar techniques and tools. What you learn in the 8D method can be used with the others, because it is the most comprehensive of all the methods.

Go to page 2 for free forms to use for your problem solving activities.

<< Previous    [1]  2    Next >>