six sigma problem solving methodology

The Easy Guide to Solving Problems with Six Sigma DMAIC Method

The most commonly used methodology in Six Sigma is the DMAIC process. Many use it to solve problems and identify and fix errors in business and manufacturing processes.

In this post, we will look at how to use the DMAIC process to solve problems. You will also find useful and editable templates that you can use right away when implementing DMAIC problem-solving in your organization.

• What are 5 the Steps of Six Sigma

DMAIC Process and Problem-Solving

Common mistakes to avoid when using six sigma dmaic methodology, how to use the dmaic methodology for problem solving in project management, what are the 5 steps of six sigma.

DMAIC is one of the core methodologies used within the Six Sigma framework. It is a data-driven method used to systematically improve the process. The approach aims to increase the quality of a product or service by focusing on optimizing the process that produces the output. This way DMAIC seeks to provide permanent solutions when it comes to process improvement.

It provides a structured problem-solving framework to identify, analyze, and improve existing processes. DMAIC guides practitioners through a series of steps to identify the root causes of process issues, implement solutions, and sustain the improvements over time.

Following we have listed down the 5 phases of the DMAIC process along with the steps you need to take when using it to solve problems. Different tools for each phase is provided with editable templates.

Step 1: Define the Problem

So there’s a problem that affects your customer or your company processes. In this first step of the DMAIC problem solving method , you need to focus on what the problem is and how it has affected you as a company.

There are a few steps you need to follow in this phase.

• Create a problem statement which should include a definition of the problem in quantifiable terms and the severity of the problem.

•  Make sure necessary resources such as a team leader and competent team members, and funds etc. are available at hand.

•  Develop a goal statement based on your problem statement. It should be a measurable and time-bound target to achieve.

•  Create a SIPOC diagram which will provide the team with a high-level overview of the process (along with its inputs, outputs, suppliers, and customers) that is being analyzed. You can also use a value stream map to do the same job.

•  Try to understand the process in more in-depth detail by creating a process map that outlines all process steps. Involve the process owners when identifying the process steps and developing the map. You can add swimlanes to represent different departments and actors responsible.

Step 2: Measure the Problem

In this step, you should measure the extent of the problem. To do so you need to examine the process in its current state to see how it performs. The detailed process map you created in the ‘Define’ phase can help you with this.

The baseline measurements you will need to look into in this phase, are process duration, the number of defects, costs and other relevant metrics.

These baseline measurements will be used as the standards against which the team will measure their success in the ‘Improve’ phase.

Step 3: Analyze the Problem

The analyze phase of the DMAIC process is about identifying the root cause that is causing the problem.

•  Referring to the process maps and value stream maps you have created, further, analyze the process to identify the problem areas.

•  Visualize the data you have collected (both in the ‘Measure’ phase and the analyze phase) to identify signs of problems in the processes.

•  Use Pareto charts, histograms, run charts etc. to represent numerical data. Study them with team leaders and process owners to identify patterns.

•  With the results of your process analysis and your data analysis, start brainstorming the root causes of the problem. Use a cause and effect diagram/ fishbone diagram to capture the knowledge of the process participants during the session.

 •  Using a 5 whys diagram, narrow down your findings to the last few causes of the problem in your process.

Step 4: Improve (Solve the Problem)

In this phase, the focus is on mitigating the root cause identified and brainstorming and implementing solutions. The team will also collect data to measure their improvement against the data collected during the ‘Measure’ phase.

•  You may generate several effective solutions to the root cause, but implementing them all would not be practical. Therefore, you will have to select the most practical solutions.

To do this you can use an impact effort matrix . It will help you determine which solution has the best impact and the least effort/ cost.

 • Based on different solutions, you should develop new maps that will reflect the status of the process once the solution has been applied. This map is known as the to-be map or the future-state map. It will provide guidance for the team as they implement changes.

•  Explore the different solutions using the PDCA cycle and select the best one to implement.  The cycle allows you to systematically study the possible solutions, evaluate the results and select the ones that have a higher chance of success.

Step 5: Control (Sustain the Improvements)

In the final phase of the DMAIC method , the focus falls on maintaining the improvements you have gained by implementing the solutions. Here you should continue to measure the success and create a plan to monitor the improvements (a Monitoring plan).

You should also create a Response plan which includes steps to take if there’s a drop in the process performance. With new process maps and other documentation, you should then proceed to document the improved processes.

Hand these documents along with the Monitoring plan and the response plan to the process owners for their reference.

Insufficiently defining the problem can lead to a lack of clarity regarding the problem statement, objectives, and scope. Take the time to clearly define the problem, understand the desired outcomes, and align stakeholders' expectations.

Failing to engage key stakeholders throughout the DMAIC process can result in limited buy-in and resistance to change. Ensure that stakeholders are involved from the beginning, seeking their input, addressing concerns, and keeping them informed about progress and outcomes.

Collecting insufficient or inaccurate data can lead to flawed analysis and incorrect conclusions. Take the time to gather relevant data using appropriate measurement systems, ensure data accuracy and reliability, and apply appropriate statistical analysis techniques to derive meaningful insights.

Getting caught up in analysis paralysis without taking action is a common pitfall. While analysis is crucial, it’s equally important to translate insights into concrete improvement actions. Strive for a balance between analysis and implementation to drive real change.

Failing to test potential solutions before implementation can lead to unintended consequences. Utilize methods such as pilot studies, simulation, or small-scale experiments to validate and refine proposed solutions before full-scale implementation.

Successful process improvement is not just about making initial changes ; it’s about sustaining those improvements over the long term. Develop robust control plans, standard operating procedures, and monitoring mechanisms to ensure the gains achieved are maintained and deviations are identified and corrected.

Applying DMAIC in a one-size-fits-all manner without considering the organization’s unique culture, context, and capabilities can hinder success. Tailor the approach to fit the specific needs, capabilities, and culture of the organization to enhance acceptance and implementation.

In the project management context, the Define phase involves clearly defining the project objectives, scope, deliverables, and success criteria. It entails identifying project stakeholders, understanding their expectations, and establishing a project charter or a similar document that outlines the project’s purpose and key parameters.

The Measure phase focuses on collecting data and metrics to assess the project’s progress, performance, and adherence to schedule and budget. Key project metrics such as schedule variance, cost variance, and resource utilization are tracked and analyzed. This phase provides insights into the project’s current state and helps identify areas that require improvement.

The Analyze phase involves analyzing the project data and identifying root causes of any performance gaps or issues. It aims to understand why certain project aspects are not meeting expectations. Techniques such as root cause analysis, Pareto charts, or fishbone diagrams can be used to identify factors impacting project performance.

In the Improve phase, potential solutions and actions are developed and implemented to address the identified issues. This may involve making adjustments to the project plan, reallocating resources, refining processes, or implementing corrective measures. The goal is to optimize project performance and achieve desired outcomes.

The Control phase focuses on monitoring and controlling project activities to sustain the improvements made. It involves implementing project control mechanisms, establishing performance metrics, and conducting regular reviews to ensure that the project remains on track. Control measures help prevent deviations from the plan and enable timely corrective actions.

What are Your Thoughts on DMAIC Problem Solving Method?

Here we have covered the 5 phases of  Six Sigma DMAIC and the tools that you can use in each stage. You can use them to identify problem areas in your organizational processes, generate practical solutions and implement them effectively.

Have you used DMAIC process to improve processes and solve problems in your organization? Share your experience with the tool with us in the comment section below.

Also, check our post on Process Improvement Methodologies to learn about more Six Sigma and Lean tools to streamline your processes.

Join over thousands of organizations that use Creately to brainstorm, plan, analyze, and execute their projects successfully.

FAQs about Six Sigma and DMAIC Approaches

What is six sigma, what is the difference between dmaic and dmadv.

DMAIC and DMADV are two methodologies used in Six Sigma. DMAIC is employed to enhance existing processes by addressing issues and improving efficiency, while DMADV is utilized for creating new processes or products that meet specific customer needs by following a structured design and verification process.

• Used for improving existing processes
• Define, Measure, Analyze, Improve, Control
• Identifies problem areas and implements solutions
• Focuses on reducing process variation and enhancing efficiency
• Used for developing new products, services, or processes
• Define, Measure, Analyze, Design, Verify
• Emphasizes meeting customer requirements and creating innovative solutions
• Involves detailed design and verification through testing

When to Use the DMAIC Methodology?

Problem identification : When a process is not meeting desired outcomes or experiencing defects, DMAIC can be used to identify and address the root causes of the problem.

Process optimization : DMAIC provides a systematic approach to analyze and make improvements to processes by reducing waste, improving cycle time, or enhancing overall efficiency.

Continuous improvement : DMAIC is often used as part of ongoing quality management efforts. It helps organizations maintain a culture of continuous improvement by systematically identifying and addressing process issues, reducing variation, and striving for better performance.

Data-driven decision making : DMAIC relies on data collection, measurement, and analysis. It is suitable when there is sufficient data available to evaluate process performance and identify areas for improvement.

Quality control and defect reduction : DMAIC is particularly useful when the primary objective is to reduce defects, minimize errors, and enhance product or service quality. By analyzing the root causes of defects, improvements can be made to prevent their occurrence.

More Related Articles

Amanda Athuraliya is the communication specialist/content writer at Creately, online diagramming and collaboration tool. She is an avid reader, a budding writer and a passionate researcher who loves to write about all kinds of topics.

How to Solve Your Problems With Lean Six Sigma (Free DMAIC Checklist)

Elisabeth Swan is the co-author of “The Problem-Solver’s Toolkit” and co-host of “The Just-in-Time Cafe Podcast.” She’s been a process improvement consultant, speaker, and innovator for over 30 years. She’s the Chief Learning Experience Officer for GoLeanSixSigma.com, a former cast member of ImprovBoston, and – if asked – may still be able to ride a unicycle.

Surgeon Atul Gawande made headlines when he told the world that a simple checklist could drastically reduce unnecessary deaths in The Checklist Manifesto .

Yet, checklists conjure images of forklift drivers on loading docks with clipboards counting boxes. How could they transform healthcare?

“ He has… produced a 90-second checklist which reduced deaths and complications by more than one-third in eight hospitals around the world – at virtually no cost and for almost any operation. ” – James Clarke, reviewing The Checklist Manifesto,  Ulster Med J. 2011 Jan; 80(1): 54.

Aviation was transformed decades earlier when management and engineers at Boeing Corporation created the pre-flight checklist after the 1935 crash of the prototype Boeing B-17 at Wright Field in Dayton, Ohio. Checklists have become so essential to the airline industry that most crashes can be traced to the misuse or failure to complete a checklist.

A New York Times reviewer noted, “no matter how expert you may be, well-designed checklists can improve outcomes”. Since the purpose of process improvement is improving outcomes, Lean Six Sigma and checklists are natural companions.

To prove that, this Process Street blog post will show the relationship between checklists and lean six sigma, and provide you with a free  DMAIC Improvement Project Tollgate Checklist that you can use right now.

Use the links below to jump to that section of the post:

Lean Six Sigma and the role of problem-solving

Lean six sigma & the checklist, introduction phase, define phase, measure phase, analyze phase, improve phase, control phase, checklists and lean six sigma, use process street to reduce error.

Or, if you just want the checklist, check it out below!

Let’s get started.

For those unfamiliar with Lean Six Sigma and process improvement, it is a structured approach for organizations to scrutinize how things are done, poke at data and processes to uncover waste and then cut out things like extra forms, out-dated approvals and other time-wasting steps.

It’s a customer-focused, 5-step problem-solving model that engages entire workforces to constantly seek a better way of doing things.

Proof of Lean Six Sigma’s influence is evident in today’s hiring practices. A poll by GoLeanSixSigma highlights that hiring managers prefer a person who is “ Green Belt Certified ” – having substantial Lean Six Sigma skills – by an almost 80% margin. In an interview with the former head of Twitter, problem-solving emerged as the top skill sought by today’s most influential hiring managers.

In other words, problem-solving (especially via Lean Six Sigma) is an absolutely vital skill.

If problem-solving is a must-have skill and checklists are key to good outcomes, then combining the two makes sense.

DMAIC – Define, Measure, Analyze, Improve & Control – is the 5-Step model for Lean Six Sigma and there’s a set of required tollgates at the end of each phase. These tollgates outline what has to be done in order to move the problem-solving process forward.

Using the tollgates as an outline, we created a dynamic  Process Street template  that you can use for free and run checklists from to track your progress!

Before you can start solving problems, you need a problem to solve.

Picking a process issue – and finding someone in leadership to support you – are two required tasks in this first tollgate. Scoping the project is important (bigger than a “just-do-it” and smaller than “solving world hunger”) but even more critical is finding a Sponsor.

Finding a Sponsor

In a poll asking Lean Six Sigma practitioners what they considered the biggest obstacle to process improvement success, “Getting Leadership Support” accounted for almost a third.

When we coach team leads who tell us they can’t find someone to back their project, we let them know, “No Sponsor, no project”. If nobody in charge has any skin in the game, there’s no point in attempting the process fix. Find a different project that leadership supports.

One thing that helps when searching for leadership backing is being able to explain what Lean Six Sigma is and why it makes a difference. Since the checklist template is dynamic we inserted a video in the Define Phase within the checklist item, “Enlist a Project Champion/Sponsor who will support you and the project”. The team lead can share the video with managers or directors who they consider Sponsor candidates.

There’s also a Project Selection Guide Template embedded in the checklist so users can take a project idea and put it through a few screening questions. Is it a repeating problem? Is there a way to measure it? The checklist serves as a reminder, a source of templates, supporting videos and other just-in-time guidance.

The next set of tollgate tasks cover the Define Phase of DMAIC. This is where problem-solvers clarify the problem, the process impacted and customers of the process.

There is a journey of discovery during this phase as everyone agrees on the issue to solve. One of the big challenges is the tendency of ambitious team leads—or equally ambitious Sponsors—to try to “shoot the moon.”

Shooting the moon

They might want to reduce cycle time, reduce defects , improve margins, and increase customer satisfaction all by next Tuesday. But a project that focuses on everything accomplishes nothing. It’s okay to measure the cost reduction that results from reducing defects. But pick one of those to be the goal. Success is more possible if you focus on one goal at a time .

It takes practice and discipline to develop a manageable goal statement. Another moon shot is aiming for perfection out of the starting gate. When we see a goal statement that claims the team will, “reduce defects from 25% to 0%” then we know there is a sizable risk of failure and disappointment.

That’s why the Define Phase of the checklist includes a Goal Builder Template along with a blog providing tips on how to create well-crafted goal statements.

The primary focus of the Measure Phase is to baseline the process. If you’re trying to reduce defects, you need to know how you’re doing at that now. What’s your track record? You need to know the baseline of the process in order to measure whether or not you made a difference with your improvement when you get to the Improve Phase.

You need to know the gap, so you can close the gap.

The data’s in the system, somewhere…

One of the issues we run into in this phase is problem solvers assuming that data is sitting in a system somewhere waiting to be accessed. If they simply run a report, they’ll have the baseline. Check that off the list. But that rarely goes according to plan.

Maybe there’s system data, but was it entered with care? Is it reliable? We’ve seen teams struggle to use data that didn’t make sense. They could access cycle time data, but it didn’t take into account that the workday ended at 5:00. I had another team looking at why healthcare invoices had to be manually adjusted. They looked up the defect codes and the biggest category was “Other”. System data existed, but it was useless.

Most of the time, it helps to collect some data manually. In order to think through your approach, you need a Data Collection Plan. That involves listing the data you want and considering things like stratification factors—the “who, what, when, where” of data. If you’re looking at defects, should you collect data on defects by product? Defects by the fields on a form? Defects by customer type?

Within the task: “Develop a Data Collection Plan with Operational Definitions and create Check Sheets as Needed”, we’ve embedded a template (The Data Collection Plan) and a video to guide the process.

You’ll learn a lot by collecting the data firsthand, so if the perfect data set is not magically sitting in the system, it helps to have a plan.

Analyze is the crux of the DMAIC method. This is where learners drill down and discover the root cause of the process problem they’ve been chasing. Once you do that, you can solve the problem for good.

But if you have not determined the root cause then you might be solving a “symptom,” putting a bandaid on the problem or implementing a change based on a hunch. All of this means there’s a high likelihood the problem will remain and the efforts will have been in vain.

Finding the smoking gun

If you’ve always been told, “don’t bring me a problem, bring me a solution,” that’s an encouragement to jump right past this step into the fun of solutions. I’ve seen teams go with their assumptions regardless of what the data says or the process analysis reveals. I’ve seen Sponsors who tell teams what solutions they want to be implemented right from the get-go.

How do you stick with analysis long enough to find the smoking gun? The trick is to keep collecting the clues in the Cause & Effect Diagram , aka The “Fishbone Diagram”. It’s an aptly named tool, popularized by Dr. Ishikawa , which resembles a fish skeleton. Its construction allows teams to develop root cause theories around a problem as they build their knowledge of the process.

Each time they collect data, interview process participants on a Gemba Walk or map the process steps, they uncover potential reasons for defects. Making the most of the Fishbone Diagram is key but, during a poll, users reported where they fell short.

Solutions masquerading as problems

Over a third of respondents reported the issues of “listing solutions” on the Fishbone instead of causes. What we hear are phrases like, “the root cause is a lack of training”.

The problem with “lack of” anything is that it’s a sneaky way of putting a solution on the Fishbone.

The question is, “what is the training addressing?” Is it lack of user knowledge? If that’s the problem, could it be solved with helpful visuals, a simpler process? There are a lot of ways to address user knowledge before jumping to more employee training.

This is when you want to behave like the persistent detective – think Columbo, the classic 70’s TV icon. Every question helps you accumulate clues. People working through the process may have the answer without knowing it. The trick is to keep looking upstream until you find potential culprits. Dig past the symptoms.

To help with this phase, the checklist includes both a Fishbone Diagram Template as well as a video on how to get the most out of the Fishbone.

The Improve Phase is a long-anticipated step in the journey. It’s the step teams generally want to jump to from the start. Testing countermeasures, piloting solutions, watching the problem disappear, that’s the fun of process improvement. If you’ve done a proper job of Define, Measure, and Analyze, this phase falls nicely into place.

The ripple effect

The catch? Unintended consequences.

If you toss a stone into a lake you can see the ripples flow out from the center. The same principle holds true for process change. If you remove a step, change a form, skip an approval , will things fall apart? For that, we look to the Failure Modes & Effects Analysis or FMEA for short.

It’s a methodical way of assessing the potential for things to go wrong. It Involves deciding the potential severity and frequency of future problems and then mistake-proofing the process to prevent them. The technique originated at NASA since they couldn’t risk trial and error when sending men to the moon. By thinking through the risks of change they developed the kind of contingency plans you saw on display in movies like Apollo 13.

That’s why there’s an FMEA Template and a video on how to use it tucked into the main checklist from this post.

It’s okay to make changes. It’s simply key to think through the impact of those changes on other parts of the business.

Process Improvement can happen quickly and have a dramatic impact, but it’s critical to “stick the landing.” The Control Phase exists to see the improvement through to stability.

If teams move on and everyone takes their eyes off the ball, things may start to slip. What they need is the ability to continuously see the performance of the new process.

Sticking the landing

Have you ever tried to watch a game without a scoreboard? How would you know who was winning? Or how much time was left?

It’s the same with process work.

How does your team know how they’re doing? How do you stay aware of how the new process is performing?

By making the data visible.

Keeping an eye on Process Performance can be done with a single metric — you need to focus on one thing. If the goal was to reduce defects, then the single metric would be tracking the daily percentage of defects. A great way to measure success is with a Control Chart.

Control Charts are time charts. You might know them as Line Charts or Run Charts. They include a measure of variation so they are often referred to as “Run Charts that went to college”. They can be created in Excel , but they can also be drawn by hand.

Teams often set up whiteboards in the shared workspace to track things like defects. People can rotate responsibility for updating the chart. If people can see the measure and are responsible for it—they pay attention to it. What gets measured gets managed.

The Control Chart Template is embedded in the checklist for the Control Phase.

Process Improvement is a mainstay of Operational Excellence and checklists are simple but effective ways to make sure you get the outcomes you want. The following quote comes from the interim CEO/President of the Association for Manufacturing Excellence ( AME ).

“ I am a big fan of checklists for ensuring quality at the source. They serve an important purpose in reminding us of all that’s needed in a particular process or project. Without checklists, we risk missing or overlooking something by mistake. Checklists work best when ticking off items as they are completed, not en masse once the entire project is done. The key point is to use and follow them, not “pencil-whip” them from memory after the fact. While not foolproof, checklists can help us cover the details and result in more thorough, successful improvement efforts. ” – Jerry Wright , President, AME

Checklists have transformed healthcare, aviation, and countless other industries. Run this Process Street DMAIC Tollgate Checklist and make sure your next improvement effort gets great results.

Process Street is a powerful piece of workflow software that lets you crush the human error in your organization.

By creating process templates (like the free DMAIC checklist in this post) you can give your whole team a central location for them to see what they have to do, and how exactly they should do it.

No more confusion, no more errors.

Take advantage of our powerful feature set to create superpowered checklists, including:

• Form fields
• Conditional logic
• Variable user permission levels
• Exporting and printing templates
• And much, much more!

Check out our intro webinar to see the app in action!

Stop leaving the success of your processes up to chance. Get started with a free trial of Process Street today!

How do you manage quality control in your business? Let us know in the comments!

Get our posts & product updates earlier by simply subscribing

Ben Mulholland

Ben Mulholland is an Editor at Process Street , and winds down with a casual article or two on Mulholland Writing . Find him on Twitter here .

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

Take control of your workflows today

• Consultancy
• Online Courses
• Lean , Lean Wiki , Six Sigma

DMAIC Model | The 5 Phase DMAIC Process to Problem-Solving

• 5 mins to read
• July 1, 2020
• By Reagan Pannell

Summary: An Introduction to DMAIC

Dmaic – the dmaic model.

The 6 Sigma DMAIC model remains the core roadmap for almost all Lean Six Sigma problem-solving approaches that drive quality improvement projects. It is used to ensure a robust problem-solving process is followed to give the best chance of the best solution being found.

A note about the structure and the approach used in this article.

Our approach to DMAIC follows Quentin Brook’s book “Lean Six Sigma & Minitab” which for anyone wishing to study Lean Six Sigma is a must for the  Green Belt Course  and the  Black Belt Course .

What is the dmaic model.

DMAIC is short for: Define, Measure, Analyse, Improve and Control. These are the key phases that each project must go through to find the right solution. This flow is the concept behind DMAIC Analysis of an issue and its the DMAIC cycle all projects must go through.

As you can quickly see from the 5 DMAIC phases they follow a logical sequence as we will go through in more detail below. But they also make sure you do not try to jump to implementing a solution before you have properly, defined and measured what you are going to be an improvement.

We all love to jump to solutions, but the DMAIC problem-solving structure helps us have a more rigorous approach so that we do not short cut the process and perhaps miss the best solution or perhaps implement the wrong solution as well. It can help companies better structure their problem-solving approaches and be more robust in their approach. 

DMAIC – The 5 DMAIC Process Phases

The phases throughout the DMAIC model have and can be broken down in many different ways. One of the best approaches we have found is from Opex Resources which shows how to examine the existing processes, and with a project team, and the sigma improvement process, we can solve complex issues.

DMAIC Define Phase

The purpose of the Define phase is ultimately to describe the problems that need to be solved and for the key business decision-makers to be aligned on the goal of the project. Its about creating and agreeing the project charter .

All too often, teams have identified solutions without actually defining what it is they will actually be trying to do or perhaps not do. This can lead to internal confusion and often solutions which completely miss the business requirements and needs.

• Define the Business Case
• Understand the Consumer
• Define The Process
• Manage the Project
• Gain Project Approval

DMAIC Measure Phase

In the measure phase, the goal is to collect the relevant information to baseline the current performance of the product or the process. In this stage, we want to identify the level of “defects” or the errors that go wrong and use the baseline to measure our progress throughout the project.

The key goal of this phase is to have a very strong and clear measure/baseline of how things are performing today so that we can always monitor our progress towards our goals. We need to understand our cycle times , process times, quality metrics.

Many projects are delivered without clear benefits being shown because the team never fully baseline the current status before making changes.

The Measure phase can be broken down into 5 key areas:

• Develop Process Measures
• Collect Process Data
• Check the Data Quality
• Understand Process Behaviour
• Baseline Process Capability and Potential

100% Free Fundamentals of Lean COURSE

Take our free course.

JOIN FOR FREE

Lean Six Sigma Yellow Belt Certification Course

We can’t solve problems by using the same kind of thinking we used when we created them” Albert Einstein Tweet

DMAIC Analyse Phase

The goal of the DMAIC Analyse phase with the lean six sigma improvement process is to identify which process inputs or parameters have the most critical effect on the outputs. In other words, we want to identify the root cause(s) so that we know what critical elements we need to fix.

During this phase, the teams need to explore all potential root causes using both analytical approaches, statistical approaches or even graphical tools such as VSM’s and Process maps to uncover the most important elements which need to be changed/fixed.

The Analyse phase can be broken down into:

• Analyse the Process
• Develop Theories and Ideas
• Analyse the Data
• and finally, Verify Root Causes 

DMAIC Improve Phase

The goal of the improvement phase is to identify a wide range of potential solutions before identifying the critical solutions which will give us the maximum return for our investment and directly fix the root cause we identified.

During this phase, the team brainstorm, pilot, test and validate potential improvement ideas before finally implementing the right solutions. With each pilot, the team can validate how well it improves the key measures they identified back in Define and Measure. When the team finally roll out the solution, the results should be seen if the right solution has been found and implemented correctly.

The Improve phase can be broken down into:

• Generate Potential Solutions
• Select the Best Solution
• Assess the Risks
• Pilot and Implement

DMAIC Control Phase

The final part of the DMAIC Model is the Control phase where we need to ensure that the new changes become business as normal and we do not revert to the same way of working as before.

During this phase, we want to ensure that we close the project off by validating the project savings and ensuring the new process is correctly documented. We also need to make sure that new measures and process KPI’s are in place and, finally that we get the business champion to sign off on both the project and the savings. We may need to redesign the workplace following the 5S principles .

The Control phase can be broken down into:

• Implement Ongoing Measurements
• Standardise Solutions
• Quantify the Improvement
• Close The Project

The key closing documents of the Control Phase is a Control Plan that documents all the changes and process steps with key risks, standard work instructions and the Project Close-Out document signed by the business owners to accept the change and the validated benefits.

The DMAIC Model vs. A3 Management vs. 8D Problem Solving

The DMAIC model is not the only project management roadmap. Two others which are important is the A3 format which originally comes from Toyota and is very Lean focused and the 8D which draws more of the DMAIC structure but with the 1-page idea of the A3.

Everyone has their own preference but each method is interchangeable. The DMAIC Structure lends its self naturally to a multi-slide Powerpoint presentation. Whereas the A3 is a single-page document which is perfect for internal communication and adding into War Rooms and Control Towers.

What’s important is that every problem-solving approach follows the PDCA (Plan, Do, Check and Act) Scientific Problem Solving format. The reset is just a preference or using the right tool in the right circumstances.

Stay current with our latest insights

• Lean Six Sigma Yellow Belt Course

Our Training Courses

Fundamentals of lean.

• Lean Six Sigma White Belt Course
• Lean Thinking Business Course
• Lean Six Sigma Green Belt Course
• Lean Six Sigma Black Belt Course

Yellow Belt Course

View all courses, recent articles, leanscape announces leadership coaching services, unlock business innovation with the lean business model canvas, 2024 recommended reads for transformative thinking, 10 best books on agile, scrum and design thinking, the ultimate guide to lean and manufacturing: boosting efficiency and productivity, 10 best management books for leaders and change makers, view all articles, green belt course, other articles, what is kanban explained in 10 minutes, an alternative to corporate training programs, why are project charters important and how to build a project charter, 04 – am i adding value, an introduction to the central limit theorem, an introduction to the anderson darling normality test, the benefits of adopting a continuous improvement approach, poka yoke: the lean concept of mistake proofing, an introduction to correlation and regression analysis, how to use multi-vari charts for better decision making, understanding the pareto principles | how do you use the 80/20 pareto rule, related articles, principle 1: use long term goals to drive short term decisions, why the fmea is a great tool for all project managers, 05 – work to establish standardised processes, what is the difference between lean & six sigma, understanding takt time | what is takt time, lean six sigma online courses.

FREE COURSE | YELLOW BELT | GREEN BELT | BLACK BELT | MASTERCLASS | WORKSHOPS

Lean Accelerator Progam

A Lean Six Sigma Green Belt Masterclass

Ready to start your journey into the world of Lean with this free course?

FREE COURSE

Lean Thinking

A Lean focused continious improvement certification course

LSS Yellow Belt

Propel your career forward, tackle complex problems and drive change

LSS Green Belt

The ultimate fast-track for future leadership

LSS Black Belt

Become an expert in change management and complex problem-solving.

Subscribe to Newsletter

Keep up to date to the latest insights, courses, training, webinars and more. Join our newsletter today.

Lean Accelerator Program

Discover the power of problem-solving, 15 min per day | 3-months | only €999 | learn from experts.

Six Sigma: The Definitive Guide

What is Six Sigma

Six Sigma (6σ, 6 sigma) is a data-driven and customer-focused approach to improving the quality and efficiency of business processes. It aims to reduce variation and defects in products or services and to achieve near-perfection in meeting customer expectations.

Six Sigma was developed by Motorola in the 1980s and popularized by General Electric in the 1990s. Since then, it has been adopted by many organizations across various sectors and domains.

The overarching premise of Six Sigma is that variation in a process leads to opportunities for error which then leads to risks for product defects. Product defects, whether in a tangible process or a service, lead to poor customer satisfaction. By working to reduce variation and opportunities for error, the Six Sigma method aims to reduce process costs and increase customer satisfaction.

When applied to business processes, Six Sigma allows companies to drastically improve their bottom line by designing and monitoring everyday business activities in ways that minimize waste and resources while increasing customer satisfaction.

Six Sigma and Statistics

At the most basic definition, Six Sigma is a statistical representation of what many experts call a “perfect” process. [1]

Technically, in a Six Sigma process, there are only 3.4 defects per million opportunities. In percentage terms, it implies that 99.99966 percent of the products from a Six Sigma process are without defects.

Six Sigma is both a methodology for process improvement and a statistical concept

that seeks to define the variation inherent in any process.

Importance of Six Sigma

According to the ATO Fact Book, the US Federal Aviation Administration’s air traffic management system handled a total of 15,416,640 flights in FY2022. [2] The table below shows the defect occurrence per million for various σ levels:

Based on a 5σ air traffic control process, errors of some type would have occurred in the process of handling approximately 3,592 flights in FY2022. With a 6σ process, that risk drops to 52.42 errors!

While most people accept a 99.9 percent (5σ) accuracy rate in even the most critical services on a daily basis, the above examples highlight how wide the gap between Six Sigma and Five Sigma really is.

For organizations, it’s not just about the error rate, it’s also about the costs associated with each error.

Consider the example of Amazon which shipped an estimated 7.7 billion packages globally in 2021 amounting to about $470 billion in sales. [3] If each erroneous order costs the company an average of $20 (a very conservative number), the cost of error for Amazon at various Sigma levels is as below:

The cost difference between a 5σ (99.99% accuracy) and a 6σ would mean over $35 million in annual savings for Amazon. From the above table, it is also evident how a drop in sigma level exponentially increases the cost a company incurs.

Origin of Six Sigma

The roots of statistical process control (SPC), which provide a backbone for Six Sigma methods, began with the development of the normal curve by Carl Friedrich Gauss [4] in the 19th century.

In the early part of the 20th century, SPC received another big boost due to several contributions from Walter Shewhart [5] , an engineer and scholar. Among his numerous contributions, two specifically stand out when speaking of Six Sigma:

First, Shewhart closely related sigma level and quality and showed that three sigma from the mean is the point where a process requires correction. Second, he introduced Control charts, which are a critical component of SPC that lets organizations maintain improved performance after a Six Sigma initiative.

During the same time, W. Edwards Deming [6] introduced the Plan-Do-Check-Act Cycle (PDCA) that stressed the importance of continuous improvement – a core tenet of Six Sigma.

Following World War II, Deming worked as a consultant to Japanese manufacturing companies and planted the ideas and concepts that would soon become the Toyota Production System or Lean Six Sigma.

In the 1980s, Bill Smith [7] moved to Motorola as the company was intensifying its quality initiatives to catch up with Japanese competitors. Bill had been brought in to share Japanese quality methods that he had learned while in the country with Motorola.

It was there that Bill Smith along with Mikel Harry [8] invented the Six Sigma improvement methodology, sharing the concept and theory with the CEO and going on to develop it thereafter.

Motorola registered Six Sigma as a service mark [9] in 1991, and as a trademark in 1993. [10] Six Sigma helped the company realize powerful bottom-line results. Motorola claims to have achieved more than $16 Billion in savings because of its Six Sigma efforts. [11]

Since then, companies as diverse as Allied Signal (now Honeywell), General Electric, Sony, Honda, Maytag, Raytheon, Texas Instruments, Bombardier, Canon, Hitachi, Lockheed Martin, and Polaroid have all adopted Six Sigma.

America’s greatest business leaders such as Larry Bossidy of Allied Signal, and Jack Welch of General Electric Company have praised Six Sigma. General Electric’s implementation of Six Sigma which took five years, reportedly resulted in $12 billion savings. [12]

Common Six Sigma principles

Organizations can impact their Sigma level by integrating the core principles of Six Sigma into leadership styles, process management, and improvement endeavors. These core principles are: [13]

Customer Focused improvement

Companies launching Six Sigma are often shocked to find out how little they understand about their customers. In Six Sigma, customer focus becomes the top priority. The measures of Six Sigma performance begin with the customer with improvements defined by their impact on customer satisfaction and value.

Process-Focused approach

Six Sigma positions the process as the key vehicle of success. From designing products and services to measuring performance to improving efficiency and customer satisfaction, Six Sigma advocates that mastering processes is the way to build a competitive advantage in delivering value to customers.

Data and fact-driven management

Six Sigma promotes the “management by fact” approach. It begins by clarifying what measures are key to gauging business performance and then gathers data and analyzes key variables. Thus, problems can be effectively defined, analyzed, and permanently resolved.

At a more down-to-earth level, Six Sigma helps managers answer two essential questions to support data-driven decisions and solutions.

• What data/information do we really need?
• How do we use that data/information to maximum benefit?

Proactive management

Six Sigma encompasses tools and practices that replace reactive habits with a dynamic, responsive, and proactive style of management. By defining ambitious goals that are reviewed frequently, priorities become clear and the focus shifts to problem prevention rather than firefighting and questioning. This often becomes a starting point for creativity and effective change.

Boundaryless collaboration

Six Sigma promotes boundarylessness collaboration that breaks down across organizational lines to improve teamwork. This unlocks opportunities through improved collaboration among companies, vendors, and customers. Billions of dollars are lost every day because of disconnects and outright competition between groups that should be working for a common cause: providing value to customers.

Drive for perfection and tolerate failure

A company that makes Six Sigma its goal will have to keep pushing to be ever more perfect while being willing to accept and manage occasional setbacks. Six Sigma techniques that improve performance also include risk management tools that limit the downside of setbacks or failures. No company will get even close to Six Sigma without launching new ideas and approaches that always involve some risk.

The Six Sigma problem-solving process: DMAIC and DMADV

Six Sigma projects that are meant to improve an existing process follow a roadmap for success known as the DMAIC process (pronounced duh-MAY-ick).

DMAIC is broken into five phases: Define, Measure, Analyze, Improve, and Control. The main activities of a DMAIC project include identifying the critical inputs or causes that are creating the problem, verifying those causes, brainstorming and selecting solutions, implementing solutions, and creating a control plan to ensure the improved state is maintained.

In some cases, teams realize that fixing an existing process may not achieve sustained improvement, instead, a process might need to be completely redesigned. In such cases, teams employ the DMADV method.

DMADV stands for Define, Measure, Analyze, Design, and Verify. The principles governing the method are similar to DMAIC, but the last two phases are geared toward rolling out and testing a completely new process.

In DMAIC define phase, the project requirements are identified, and goals for success are set. Requirements and goal setting might relate to a variety of factors and are dependent on guidance from the leadership and expected budgets.

In a DMADV project, the define phase is more rigid. The teams must also define customer requirements to create a measuring stick to which the process development can be compared.

In both DMAIC and DMADV, teams create a project charter and a basic work plan. A charter is a synopsis of the project and provides common information and a summary of what the team hopes to accomplish. The charter also features a list of team members, names of those responsible for outcomes, a problem statement, a goal, and some basic definitions of scope and metrics for success.

Tools like the SIPOC diagram and Stakeholder Analysis(discussed later) can be used to understand processes and key stakeholders.

The bulk of the measure phase in DMAIC is occupied with gathering data and formatting it in a way that can be analyzed. Teams build tools to capture data, create queries for digital data, sift through enormous amounts of data to find relevant information or capture data by hand in some manual process.

The Measure stage validates assumptions from the Define stage with actual data. It might be required to revisit problem statements, goals, and other process-related definitions. The define stage creates a “rough draft” while the measure converts that into a final one.

In DMADV, the approach is similar, but activities are typically more targeted. Teams collect data and measurements that help define performance requirements for the new process.

Deciding what to measure can be challenging and requires strong observation skills, an understanding of the reasons behind the measure, knowledge of data types such as discrete and continuous, tools for measurement assessment, and a strong background in statistical analysis.

In the Analyze phase of DMAIC, hypotheses are developed about causal relationships between inputs and outputs. Causations are narrowed down to the vital few using methods such as the Pareto analysis (discussed later). Using statistical analysis and data, hypotheses and assumptions are validated.

In a DMAIC project, Analyze phase tends to flow into the Improve phase. Hypothesis testing, assumption validation and possible solutions might begin in Analyze and continue into the Improve phase.

Likewise, in a DMADV project, teams also identify cause-and-effect relationships, but they are more concerned with identifying best practices and benchmarks by which to measure and design the new process.

Teams begin the process design work by identifying value-added and non-value-added activities, locating areas where bottlenecks or errors are likely, and refining requirements to meet the needs and goals of the project.

The lines between Measure and Analyze are often blurrier than the lines between Define and Measure. In some cases, a team must measure, analyze, and then measure some more, particularly if metrics aren’t already in place for a process.

During the Analyze phase, teams use a variety of tools like Pareto Charts, Run Charts, Histograms, Cause-And-Effect Diagrams, Scatter Diagrams, Process Maps, and Value Analysis (all of which are discussed later).

Improve or Design

Six Sigma teams start developing the ideas that began in the Analyze phase during the Improve phase of a project by using statistics and real-world observation to test hypotheses and solutions.

Solutions are standardized in preparation for rolling improved processes to daily production and non-team employees. Teams also start measuring results and laying the foundation for controls that will be built in the last phase.

In the Improve phase, the DMADV project begins to diverge substantially. New processes are designed, which does involve some solutions testing (as in DMAIC), but also mapping workflow principles and actively building new infrastructures.

This might mean putting new equipment in place, hiring and training new employees, or developing new software tools.

As solutions are narrowed down, more than one might appear compelling and it can get challenging to determine which of the solutions improve a process. In such cases, changes are implemented one at a time and verified before moving on to the next.

Tools like the Solutions Selection Matrix (discussed later) can be used to evaluate and choose the best solutions.

Control or Verify

Control/Verify phase is where loose ends are tied and the project is transitioned to a daily work environment. Controls and standards are established so that improvements can be maintained and the responsibility for those improvements is transitioned to the process owner.

In DMAIC, teams usually handle four tasks:

• creating the foundation for process discipline
• finalizing documents related to the improvement
• establishing ongoing metrics to evaluate the process
• and building a process management plan that lets the team transition the improvement to the process owner.

Tools during the Control phase include documentation checklists, control charts, response plans, process maps, and process dashboards.

Verify phase of DMADV is like the Control phase, but with the exception that teams might perform further critical-to-quality (CTQ) analysis (discussed later) at the end of a project to identify new CTQ factors.

This is essential as the process/product could be different from when the team started working. At the end of the Verify phase, the final product or a process that meets the needs first identified in the Define stage is delivered.

When to use DMAIC and DMADV?

Why are the DMAIC and DMADV models effective?

The DMAIC/DMADV model provides seven key advantages:

• Measuring the problem: In DMAIC, teams just don’t assume that they understand the problem, they are required to prove (validate) it with facts.
• Focus on the customer: The process always considers the external customer’s interests which is important, especially when an organization is trying to cut costs in a process.
• Verifying root cause: Teams agreeing on a cause is not proof enough. Teams must prove their cause with facts and data.
• Breaking old habits: DMAIC/DMADV projects have proven to go beyond minor changes in crusty old processes and drive real change and results through creative new solutions.
• Managing risks: Testing and perfecting solutions is embedded within the process which mitigates risks.
• Measuring results: Solutions and their impact are verified through facts with goals and metrics clearly defined.
• Sustaining change: Even the best of new “best practices” developed by a DMAIC team can die quickly if not nurtured and supported. Making change is the final key and part of this problem-solving approach.

The Six Sigma toolkit

Any technique that helps better understand, manage, and improve a business or a process can qualify as a Six Sigma tool, but some of them are key to planning and executing Six Sigma projects.

Understanding these tools gives a clearer perspective on how Six Sigma works. These tools are bunched into four categories:

Tools for generating ideas and organizing information

Tools for data gathering, tools for process and data analysis, tools for statistical analysis.

The goal of this article is to provide a quick overview of each of these tools. More details and how-to information can be found in a variety of other books and websites.

1. Brainstorming

Many Six Sigma methods have brainstorming, or idea generation, as a starting point. Brainstorming is an idea-creation method for generating many creative ideas in a short period. Brainstorming can be used when:

• A broad range of options is to be generated
• Creative, original ideas are required
• Group participation is desired

During a brainstorming session, all ideas are to be treated as valid and worthy of consideration. At this stage, ideas are not criticized or evaluated. They are to be recorded as-is without discussion. Even combining, modifying, and expanding on others’ ideas is encouraged.

Methods like the “Sticky Storm Technique” [14] that combines individual and group brainstorming can be used.

2. Affinity Diagramming

The Affinity Diagram [15] (also known as Affinity Chart, Affinity Mapping, K-J Method, or Thematic Analysis) groups ideas according to their natural relationships. It usually follows the brainstorming stage to help organize the output.

It can be used to organize and consolidate information related to a product, process, complex issue, or problem. Ideas are grouped according to their affinity or similarity.

Teams creating affinity diagrams record each idea on a note or a card. They then look for relationships between individual ideas and have team members simultaneously sort the ideas into five to ten related groupings. The process is repeated until all ideas are grouped.

It is okay to have “loners” that don’t seem to fit a group. It is also okay to move a note someone else has already moved. If a note seems to belong to two groups, a second note can be made.

It is important to avoid talking during this process. The focus should be on looking for and grouping related ideas without attaching any priority or importance to them.

3. Multivoting

Multivoting [16] narrows a large list of possibilities to a smaller list of top priorities. Each participant gets a certain number of votes (unlike a single vote in straight voting). This allows an item that is favored by all, but not the top choice of any, to rise to the top.

Multivoting can be used:

• After brainstorming generates a long list of possibilities
• When a list must be narrowed down
• When a decision must be made by group judgment

4. Structure Tree (Tree Diagram)

A Structure Tree [17] (also known as Systematic Diagram, Tree Analysis, Analytical Tree, or Hierarchy Diagram) is used to depict the hierarchy of tasks and subtasks needed to complete an objective.

The tree diagram starts with one item that branches into two or more, each of which branches into two or more, and so on. The finished diagram bears a resemblance to a tree, with a trunk and multiple branches.

As seen from the figure above, a tree diagram breaks down broad categories into finer levels of detail. Developing the tree diagram helps teams to think step by step from generalities to specifics.

A tree diagram can be used when:

• An issue, that is known in broad generalities must move to specific details
• Developing actions to carry out a solution or a plan
• Analyzing processes in detail
• Probing for the root cause of a problem
• Evaluating implementation issues for several potential solutions
• After an affinity diagram or interrelationship diagram has uncovered key issues
• As a communication tool, to explain details to others

5. High-level process map (SIPOC diagram)

SIPOC [19] (pronounced “sye-pahk”) is an acronym for Supplier, Input, Process, Output, Customer. SIPOC is used in the Define phase of DMAIC and is often a preferred method for diagramming major business processes and identifying possible measures.

SIPOC shows the major activities or sub-processes in a business in a systematic framework represented by the Suppliers, Inputs, Processes, Outputs, and Customers. This helps identify the boundaries and critical elements of a process without losing sight of the big picture.

In a SIPOC diagram, suppliers are the sources for the process, inputs are the resources needed for the process to function, the process constitutes the high-level steps that the system/organization undertakes, outputs are the results of those processes and customers are the people who receive outputs or benefit from the process.

Creating a SIPOC diagram helps answer the following questions:

• How can a process be made easier?
• Is a quality product delivered to the customers?
• Can supplier management be improved?
• Are suppliers delivering as per need?
• Are the customer persona and the demographics they fall into known?
• Are there any inefficiencies that can improve when creating the product?

Sometimes, a variation of the SPCIF diagram called SIPOC+CM [21] is used that also maps the Constraints (C) and the Measures (M).

6. Flowchart

A Flowchart [22] is used to show details of a process, including tasks and procedures, alternative paths, decision points, and rework loops. While simple flowcharts can be constructed with a bunch of stickies on a wall, complex ones are developed using advanced software [23] that offers extensive capabilities.

A flowchart is a visual representation of distinct steps of a process in sequential order. Elements that may be included in a flowchart are a sequence of actions, materials or services entering or leaving the process (inputs and outputs), decisions that must be made, people who become involved, time involved at each step, and/or process measurements.

Flowcharts can be used:

• To develop an understanding of how a process is done
• To study a process for improvement
• To communicate to others how a process is done
• For better communication among people involved with the same process
• To document a process
• When planning a project

7. Fishbone diagram

A Fishbone diagram [25] (also known as Cause-And-Effect Diagram, Ishikawa Diagram) is used to brainstorm possible causes of a problem (or effect) and puts the possible causes into groups or affinities. Causes that lead to other causes are linked similarly to a structure tree.

The fishbone diagram helps gather collective ideas from the team on where a problem might arise and enables the team members to think of all possible causes by clarifying major categories.

While a fishbone diagram does not reveal the right cause, it helps develop educated guesses, or hypotheses, about where to focus measurement and further root cause analysis.

A fishbone diagram can be used:

• When identifying possible causes for a problem
• When a team’s thinking tends to diverge

8. Critical to Quality (CTQ) tree

A CTQ tree [27] is a visual tool to identify and prioritize the critical quality characteristics (CTQs) that are most important to customers. It helps map the relationship between customer requirements and specific product or process characteristics for improvement focus.

A CTQ tree starts by identifying the customer needs and then branches into drivers and requirements. Building a CTQ tree requires identifying:

• The Need: This is the actual product or service that a customer wants.
• The Drivers: These are quality drivers that must be present to fulfil customer needs.
• The Requirements: These are the list of the requirements for each driver. In other words, recording measurable performance metrics for each driver.

In Six Sigma, once an organization has completed the Voice of Customer (VOC) process, it is useful to build a CTQ tree to:

• Bring more clarity in understanding customer needs
• Identifying current issues and improving the product or service
• Help design or develop a product or service during the early stages of the process
• Stand out from competitors

1. Sampling

Sampling [28] is the selection of a set of elements from a target population or product lot. Sampling is used frequently as gathering data on every member of a target population or every product is often impossible, impractical, or too costly.

Sampling helps draw conclusions or make inferences about the population or product lot from which the sample is drawn.

When used in conjunction with randomization [29] (randomly selecting factors, measurements, or variables to eliminate the effects of bias or chance), samples provide virtually identical characteristics relative to those of the population or product grouping from which the sample was drawn.

Teams must be careful to avoid sampling errors which are primarily of three kinds:

• Bias (lack of accuracy)
• Dispersion (lack of precision)
• Non-reproducibility (lack of consistency)

2. Operational Definitions

An Operational Definition [30] is a clearly defined description of some characteristic. It should be specific and describe not only what is being measured but how. An operational definition needs to be agreed upon by all parties, whether that is a customer or an internal function of the organization.

For example, an Amazon search for “blue shirt” will yield the following result:

This is the key purpose of an operational definition. Everyone must define, measure, and interpret things the same way.

3. Voice Of The Customer (VOC) Methods

Voice Of the Customer (VOC) [31] is the direct input and expression of the wants, needs, and expectations that the customer has for the organization with which the customer conducts business.

In Six Sigma, VOC is the structured process of directly soliciting and gathering the specifically stated needs, wants, expectations and performance experiences of the customer about the products and/or services that an organization provides.

There are several ways an organization can capture the VOC, such as:

• Direct observations
• Focus groups
• Complaint data
• Customer service reps
• Existing company data
• Industry data

Unintended miscommunication between an organization and its customers is a common reason why organizations lose customers and their business. It is critical for an organization to understand the VOC and customer requirements.

4. Checksheets

A Checksheet [33] (also called a defect concentration diagram) is a structured, prepared form for collecting and analyzing data. It is a generic data collection and analysis tool that can be adapted for a wide variety of purposes and is considered one of the seven basic quality tools.

A checksheet can be used when:

• Data can be observed and collected repeatedly by the same person or at the same location.
• Collecting data on the frequency or patterns of events, problems, defects, defect location, defect causes, or similar issues.
• Collecting data from a production process.

Checklists have two key objectives:

• Ensure that the right data is captured, with all necessary facts included, such as when it happened, how many, and what customer. These facts are called stratification factors. [32]
• To make data gathering as easy as possible for the collectors.

Checksheets can vary from simple tables and surveys to diagrams used to indicate where errors or damage occurred. Spreadsheets are the place where checksheet data is collected and organized. A well-designed spreadsheet makes it much easier to use the data.

5. Measurement Systems Analysis (MSA)

A measurement systems analysis (MSA) [34] is an umbrella term covering various methods used to ensure that measures are accurate and reliable. MSA evaluates the test method, measuring instruments, and the entire process of obtaining measurements to ensure the integrity of data used for analysis and to understand the implications of measurement error for decisions made about a product or process.

An MSA considers the following:

• Selecting the correct measurement and approach
• Assessing the measuring device
• Assessing procedures and operators
• Assessing any measurement interactions
• Calculating the measurement uncertainty of individual measurement devices and/or measurement systems

Common tools and techniques of measurement systems analysis include calibration studies, fixed effect ANOVA [35] , components of variance, attribute gage study, gage R&R, ANOVA gage R&R [36] , and destructive testing analysis.

The goals of MSA are:

• Quantification of measurement uncertainty, including the accuracy, precision, repeatability, reproducibility, and discrimination
• Quantifying the stability and linearity of these quantities over time and across the intended range of use of the measurement process.
• Development of improvement plans, when needed.
• Deciding if a measurement process is adequate for a specific engineering or manufacturing application.

Checking on people performing the measurements is also a part of MSA.

1. Process-Flow Analysis

A process flow analysis uses the process map or a flowchart as input to scrutinize the process for redundancies, unclear hand-offs, unnecessary decision points, and so on. Process data can reveal problems such as delays, bottlenecks, defects, and rework.

A process flow analysis can be one of the quickest ways to find clues about the root causes of problems.

2. Value and Non-Value-Added Analysis

Activities usually fall under three kinds:

• Value-added activities
• Non-value-added activities
• Business value-added activities

Value-added activities are those activities for which the customer is willing to pay for and non-value-added activities are those for which the customer is not willing to pay.

Business value-added activities are those for which the customer is not willing to pay but are necessary for the running of processes and the business. These could include work performed for audits, controls, risk management, regulatory requirements, etc.

In Six Sigma, both non-value-added and business value-added activities are considered “wastes” but are segregated and treated differently.

Wastes can be identified using the following questions:

• Does the activity transform the form, feature, feeling and function that the customer is willing to pay for?
• Is it being done right the first time?
• Is this something the customer expects to pay for?

A positive answer or a “yes” to all of them indicates that it is a value-added activity. Even a single “No” indicates that it is either a non-value-added activity or a business value-added activity.

It’s never possible to eliminate all non-value-adding activities, especially Business value-added activities, But this approach helps in reducing the non-essential aspects of a process that are a drain on resources.

3. Charts and Graphs:

The first and best way to analyze measures of a process is to create a picture of the data and charts and graphs help accomplish just that. Visual representation of data becomes a lot more meaningful and convenient to read than a table of numbers.

Charts and graphs help make discoveries that the numbers themselves would hide. Charts and graphs are of various types, each offering a bit different picture of the data.

Following are some of the most used types of charts and graphs:

Pareto Chart

A Pareto is a specialized bar chart that breaks down a group by categories and compares them from largest to smallest. It’s used to look for the biggest pieces of a problem or contributors to a cause. Learn more about Pareto analysis .

Histogram (Frequency Plot)

A histogram is a type of bar chart that shows the distribution or variation of data over a range: size, age, cost, length of time, weight, and so on. (A Pareto chart, by contrast, slices data by category)

In analyzing histograms, teams can look for the shape of the bars or the curve, the width of the spread, or range, from top to bottom, or the number of “humps” in the bars. When customer requirements are plotted on a histogram, it reveals how much what’s being done meets or does not meet customers’ needs.

Run (Trend) Chart

Pareto charts and histograms don’t reveal the time dimension, i.e. how things change over time. A run chart accomplishes just that.

Consider the below example of a chemical process that is sensitive to ambient temperature. It can be visually inferred that the temperatures during the months of April through July have a negative bearing on the process leading to defects.

Control Chart

A control chart is also used to study how a process changes over time. Data are plotted in time order. But unlike a Run Chart, a Control Chart always has a central line for the average, an upper line for the Upper Control Limit (UCL), and a lower line for the Lower Control Limit (LCL). These lines are determined from historical data.

Any data point falling between the UCL and the LCL is considered as safe. The data points falling outside the LCL and the UCL are called ‘Outliers’. All outliers are candidates for Root Cause Analysis.

Control charts are used for:

• Controlling ongoing processes by finding and correcting problems as they occur
• Predicting the expected range of outcomes from a process
• Determining whether a process is stable (in statistical control)
• Analyzing patterns of process variation from special causes (non-routine events) or common causes (built into the process)
• Determining whether a quality improvement project should aim to prevent specific problems or to make fundamental changes to the process

Scatter Plot (Correlation) Diagram

A Scatter plot looks for direct relationships between two factors in a process, usually to see whether they are correlated, meaning that a change in one is linked to a change in the other.

When an increase in one factor matches an increase in the other, it’s a “positive correlation” and likewise the reverse is a “negative correlation”. If two measures show a relationship, one may be causing the other.

However, a correlation does not necessarily mean causation. The underlying connection may be hidden. For example, there is a statistical correlation between eating ice cream and drowning incidents, but ice cream consumption does not cause drowning. They are connected by a third common cause which is warm summer weather.

A scatter plot helps a DMAIC team visualize the relationship between process output (Y) and suspected cause/input factors (X). As a practice, X is plotted on the horizontal axis (independent variable), while Y is plotted on the vertical axis (dependent variable).

In some cases, collected data is not accurate enough. Analysis of such data requires a level of proof beyond what visual tools can offer. Six Sigma teams apply more sophisticated statistical analysis tools in such cases.

The statistical part of the toolkit contains many different tools and formulas. Some of the broad families of statistical methods are:

Tests of statistical significance

These tools look for differences in groups of data to see whether they are meaningful. These tests include Chi-square, t-tests, and analysis of variance. [39]

Correlation and regression

These tools are similar to a scatter plot but can get a lot more complex, including regression coefficients, simple linear regression, multiple regression, surface response tests, and so on. These tools test for the presence, strength, and nature of the links among variables in a process or a product, such as how tire pressure, temperature, and speed would affect gas mileage. [40]

Design Of Experiments (DOE)

DOE deals with planning, conducting, analyzing, and interpreting controlled tests to evaluate the factors that control the value of a parameter or group of parameters. DOE is a powerful data collection and analysis tool that can be used in a variety of experimental situations.

It allows for multiple input factors to be manipulated, determining their effect on a desired output (response). DOE can identify important interactions that may be missed when experimenting with one factor at a time.[ 41]

Tools for implementation and process management

1. project management methods.

Six Sigma companies recognize early on the importance of strong project management skills: planning, budgeting, scheduling, communication, and people management. Technical project management tools such as Gantt chart scheduling can be used for implementation and process management.

2. Potential Problem Analysis (PPA) and Failure Mode and Effects Analysis (FMEA)

PPA is a systematic method for determining what could go wrong in a plan under development. The problem causes are rated according to their likelihood of occurrence and the severity of their consequences. Preventive actions are taken, and contingency plans are developed. The process helps to create a smooth, streamlined implementation process. [42]

Similarly, FMEA is a step-by-step approach for identifying all possible failures in a design, a manufacturing or assembly process, or a product or service. It is a common process analysis tool. FMEA begins during the earliest conceptual stages of design and continues throughout the life of the product or service. [43]

3. Stakeholder Analysis

Complex change can affect a lot of people. Six Sigma teams recognize that for change to be successful, it is important to consider the needs and perspectives of various parties involved, i.e. the stakeholders.

The Stakeholder Analysis [44] process is used to determine who the stakeholders are, what are their wants, goals, and concerns and how best to understand mutual interests.

Stakeholders are grouped based on their interest in the project outcome and the power they hold in influencing the change. They usually fall under four categories, each of which needs a different approach to drive successful change:

4. Force Field Diagram

A Force Field Diagram is a result of a force field analysis that shows the relationship between factors that help promote a change vs. those that oppose or create resistance. Like stakeholder analysis, the force field is used to develop plans to build support for a critical change.

A force field diagram helps the team to focus on improving the driving forces and weakening the resisting forces through education or refinements.

5. Balanced Scorecards

The balanced scorecard [45] is a strategic management tool that views the organization from different perspectives, usually the following:

• Financial: The perspective of shareholders
• Customer: How customers experience and perceive an organization
• Business process: Key processes used to meet and exceed customer/shareholder needs
• Learning and growth: How to foster ongoing change and continuous improvement

A balanced scorecard provides feedback on both internal business processes and external outcomes to continuously improve strategic performance and results.

6. Solution Selection Matrix

A Solution Selection Matrix (SSM), also known as a Decision Matrix or a Criteria Matrix, is a tool used to objectively assess the strengths and weaknesses of each option and determine the best course of action.

SSM consists of a table or a grid of options and criteria. Each criterion represents a specific aspect or attribute that is important in evaluating the options. The evaluator assigns a rating or score to each option for each criterion.

Once the ratings are assigned, they are often weighted (by assigning a numerical value) to indicate the relative importance. A weighted score is then calculated for each option by multiplying the rating by the corresponding weight.

The option with the highest overall score indicates the most favorable choice. SSM provides a structured and systematic approach to decision-making, helping to eliminate bias and subjectivity.

7. Process Dashboards

A Process Dashboard is a vital decision management tool that showcases essential information about process performance to process participants and owners. It provides high-maturity, metrics-intensive data necessary for process analysis and decision-making.

8. Process Documentation

As a DMAIC project reaches a conclusion with solutions in place and results in hand, the Six Sigma team must turn over responsibility to those who will manage the process on an ongoing basis.

Creating effective, clear, not overly complex process documentation that includes process maps, task instructions, measures, and more is the last and most important element of the DMAIC Control step.

Note on Six Sigma tools

While Six Sigma is rich with tools that help make better decisions, solve problems, and manage change, Six Sigma and the tools are one and the same.

Using too many tools can complicate things. Demanding that they be used when they aren’t helpful can undermine the goals of Six Sigma just as easily as not using tools.

The following are important considerations when selecting a Six Sigma tool:

• Use only the tools that help in getting the job done.
• Keep it as simple as possible.
• When a tool isn’t helping, stop and try something else.

Six Sigma breakthrough equation

Six Sigma looks at every process through what is known as the breakthrough equation shown below:

• Y is the outcome(s) or result(s) desired or needed.
• X represents the inputs, factors, or pieces necessary to create the outcome(s). There can be more than one Xs.
• ƒ is the function, the way or process by which the inputs are transformed into the outcome.
• ε (epsilon) is the presence of error or uncertainty surrounding how accurately the Xs are transformed to create the outcome.

In any process, a set of input variables are transformed by a function (or process) and combined with error to form the output. The Y results from, or is a function of, the Xs.

In the bread-making example above, bread is the Y (output). Inputs like the dough, salt, yeast etc., are the Xs while the process of dough making and baking are the ƒ. Errors like wrong temperature leading to improper baking represent the epsilon (ε).

Basic Metrics in Six Sigma

When applying Six Sigma to processes and improvements, the below metrics are used to access and measure process accuracy levels:

Defects Per Unit (DPU)

DPU is a measure of how many defects there are in relation to the number of units tested.

It is concerned with total defects, and one unit could have more than one defect.

For example, if a publisher printed 1,000 books and pulled out 50 books for quality checks,

that revealed:

• 3 books are missing pages
• 1 book is missing pages and has a torn cover
• 2 books have loose spines
• 1 book has incorrect printing and incorrect alignment

There are 9 total errors in a sample size of 50 books, hence the DPU is calculated as:

DPU provides an average level of quality. It tells how many defects on average each unit can be expected to have. In this case, that is 0.18 defects on average.

Defects per Opportunity (DPO)

DPO is the number of defects in a sample divided by the total number of defect opportunities.

In the above example, each book has a possibility of 5 types of errors (missing page, torn cover, loose spine, incorrect printing, and incorrect alignment). Hence the opportunity for error in each book is 5 and DPO is calculated as:

Defects per Million Opportunities (DPMO)

This represents a ratio of the number of defects in one million opportunities. In other words, how many times did a flaw or mistake (defect) occur for every million opportunities there were to have a flaw or a mistake?

DPMO is also the same as DPO multiplied by a million. By scaling the sample size to a common value (1 million), DPMO allows to compare accuracy levels of different processes.

In the book example, DPMO is calculated as:

First-Time Yield (FTY)

FTY is the ratio of units produced to units attempted to produce.

For example, if 100 cookies were put in the oven, but only 95 came out edible, then:

Most products or services are created via multiple processes, in which case FTY for each process needs to be multiplied to calculate an overall FTY.

Rolled Throughput Yield (RTY)

RTY provides a probability that a unit will be generated by a process with no defects.

One of the main differences between RTY and FTY is that RTY considers whether rework was needed to generate the number of final units. This is valuable as organizations don’t always think about the rework that is inherent in a process, which means they often measure a process and deem it successful even if waste is present.

Consider the following process chain:

The RTY is calculated as follows:

RTY for Process A: 100 – (5 + 5) = 90, 90/100 = 0.9

RTY for Process B: 95 – (10 + 5) = 80, 80/95 = 0.84

RTY for Process C: 85 – (5 + 15) = 65, 65/85 = 0.76

Overall RTY = 0.9 * 0.84 * 0.76 = 0.574

While RTY does not indicate final production or sales, a low RTY indicates that there is waste in the process in the form of rework.

Six Sigma vs. Lean Six Sigma

While Six Sigma focuses on eliminating defects and reducing variation, Lean Six Sigma (LSS) focuses on eliminating waste and improving speed. LSS combines Lean Management and Six Sigma to increase the velocity of value creation.

During the 2000s, Lean Six Sigma forked from Six Sigma and became its own unique process. LSS developed as a specific process of Six Sigma, incorporating ideas from lean manufacturing, which was developed as a part of the Toyota Production System in the 1950s.

Lean Six Sigma is more specifically used to streamline manufacturing and production processes, while Six Sigma methodologies can benefit any business.

Six Sigma Training Levels and Roles

Possessing a Six Sigma certification proves that an individual has demonstrated practical applications and knowledge of Six Sigma. These certification levels are differentiated by belt level.

The belt color someone holds will help to determine what role they will play in a given project and how they will be spending their time. Broadly they are shown as below:

In addition to the above levels, there is Six Sigma Champion which is not a belt per se but plays a crucial role in Six Sigma projects and organizations.

The primary function of the Champion is to ensure that all operational projects align with strategic business objectives.

1. “Six SIGMA: A Complete Step-By-Step Guide: A Complete Training & Reference Guide for White Belts, Yellow Belts, Green Belts, and Black Belts”. Six Sigma Council, https://www.sixsigmacouncil.org/wp-content/uploads/2018/08/Six-Sigma-A-Complete-Step-by-Step-Guide.pdf . Accessed 06 Jul 2023

2. “Air Traffic By The Numbers”. Fedaral Avaiation Administration, https://www.faa.gov/air_traffic/by_the_numbers . Accessed 06 Jul 2023

3. “How many Amazon packages get delivered each year?”. The Conversation, https://theconversation.com/how-many-amazon-packages-get-delivered-each-year-187587 . Accessed 06 Jul 2023

4. “Carl Friedrich Gauss”. Wikipedia, https://en.wikipedia.org/wiki/Carl_Friedrich_Gauss . Accessed 06 Jul 2023

5. “Walter A Shewhart”. Sixsigmastudyguide, https://sixsigmastudyguide.com/shewhart/ . Accessed 06 Jul 2023

6. “Edwards Deming”. Wikipedia, https://en.wikipedia.org/wiki/W._Edwards_Deming . Accessed 08 Jul 2023

7. “Bill Smith”. Wikipedia, https://en.wikipedia.org/wiki/Bill_Smith_(Motorola_engineer) . Accessed 08 Jul 2023

8. “Mikel Harry”. Wikipedia, https://en.wikipedia.org/wiki/Mikel_Harry . Accessed 08 Jul 2023

9. “Trademark Status & Document Retrieval (TSDR)”. The United States Patent and Trademark Office (USPTO), https://tsdr.uspto.gov/#caseNumber=1647704&caseSearchType=US_APPLICATION&caseType=SERIAL_NO&searchType=statusSearch . Accessed 08 Jul 2023

10. “SIX SIGMA – Trademark Details”. Justia, https://trademarks.justia.com/741/99/six-74199225.html . Accessed 08 Jul 2023

11. “The History of Six Sigma”. Isixsigma, https://www.isixsigma.com/history/history-six-sigma/ . Accessed 08 Jul 2023

12. “Six Sigma Case Study: General Electric”. 6sigma, https://www.6sigma.us/ge/six-sigma-case-study-general-electric/ . Accessed 08 Jul 2023

13. “What Is Six Sigma?”. Peter S. Pande, Lawrence Holpp, https://books.google.co.in/books/about/What_Is_Six_Sigma.html?id=vBzaUJuH8hYC&redir_esc=y . Accessed 10 Sep 2023

14. “BRAINSTORMING”. American Society for Quality, https://asq.org/quality-resources/brainstorming . Accessed 08 Jul 2023

15. “WHAT IS AN AFFINITY DIAGRAM?”. American Society for Quality, https://asq.org/quality-resources/affinity . Accessed 08 Jul 2023

16. “WHAT IS MULTIVOTING?”. American Society for Quality, https://asq.org/quality-resources/multivoting . Accessed 08 Jul 2023

17. “WHAT IS A TREE DIAGRAM?”. American Society for Quality, https://asq.org/quality-resources/tree-diagram . Accessed 08 Jul 2023

18. “Tree Diagram: All you need to know about it”. Qidemy, https://qidemy.com/tree-diagram-all-you-need-to-know-about-it/ . Accessed 08 Jul 2023

19. “What is a SIPOC diagram? 7 steps to map and understand business processes”. Asana, https://asana.com/resources/sipoc-diagram . Accessed 08 Jul 2023

20. “SIPOC”. Wikipedia, https://en.wikipedia.org/wiki/SIPOC . Accessed 08 Jul 2023

21. “SIPOC+CM DIAGRAM”. American Society for Quality, https://asq.org/quality-resources/sipoc . Accessed 08 Jul 2023

22. “WHAT IS A FLOWCHART?”. American Society for Quality, https://asq.org/quality-resources/flowchart . Accessed 08 Jul 2023

23. “Comparison of Business Process Model and Notation modeling tools”. Wikipedia, https://en.wikipedia.org/wiki/Comparison_of_Business_Process_Model_and_Notation_modeling_tools . Accessed 08 Jul 2023

24. “Flowchart”. Wikipedia, https://en.wikipedia.org/wiki/Flowchart . Accessed 09 Jul 2023

25. “FISHBONE DIAGRAM”. American Society for Quality, https://asq.org/quality-resources/fishbone . Accessed 09 Jul 2023

26. “Ishikawa diagram”. Wikipedia, https://en.wikipedia.org/wiki/Ishikawa_diagram . Accessed 09 Jul 2023

27. “Critical to Quality Tree (CTQ)”. Minnesota Department of Health, https://www.health.state.mn.us/communities/practice/resources/phqitoolbox/ctqtree.html . Accessed 10 Jul 2023

28. “WHAT IS SAMPLING?”. American Society for Quality, https://asq.org/quality-resources/sampling . Accessed 11 Jul 2023

29. “Randomization: Key to Reducing Bias and Increasing Accuracy”. Isixsigma, https://www.isixsigma.com/dictionary/randomization/ . Accessed 09 Jul 2023

30. “Operational Definition”. Isixsigma, https://www.isixsigma.com/dictionary/operational-definition/ . Accessed 09 Jul 2023

31. “How to Use Voice of the Customer to Improve Customer Experience”. Isixsigma, https://www.isixsigma.com/dictionary/voice-of-the-customer-voc/ . Accessed 09 Jul 2023

32. “WHAT IS STRATIFICATION?”. American Society for Quality, https://asq.org/quality-resources/stratification . Accessed 09 Jul 2023

33. “CHECK SHEET”. American Society for Quality, https://asq.org/quality-resources/check-sheet . Accessed 11 Jul 2023

34. “Measurement System Analysis (MSA)”. Lean6sigmapro, https://www.lean6sigmapro.com/knowledgebase/msa . Accessed 09 Jul 2023

35. “Distinguishing Between Random and Fixed: Variables, Effects, and Coefficients”. Portland State University, https://web.pdx.edu/~newsomj/mlrclass/ho_randfixd.pdf . Accessed 09 Jul 2023

36. “ANOVA gauge R&R”. Wikipedia, https://en.wikipedia.org/wiki/ANOVA_gauge_R%26R . Accessed 09 Jul 2023

37. “Control Chart”. Project Management Research Institute, https://pmri.in/dictionary/control-chart/ . Accessed 10 Jul 2023

38. “Data Demystified: Correlation vs. Causation”. Datacamp, https://www.datacamp.com/blog/data-demystified-correlation-vs-causation . Accessed 09 Jul 2023

39. “Tests of Statistical Significance”. California State University, Long Beach, https://home.csulb.edu/~msaintg/ppa696/696stsig.htm . Accessed 09 Jul 2023

40. “Statistics review 7: Correlation and regression”. National Library of Medicine , https://www.ncbi.nlm.nih.gov/pmc/articles/PMC374386/ . Accessed 09 Jul 2023

41. “WHAT IS DESIGN OF EXPERIMENTS (DOE)?”. American Society for Quality, https://asq.org/quality-resources/design-of-experiments . Accessed 09 Jul 2023

42. “Potential Problem Analysis”. Digital Healthcare Research, https://digital.ahrq.gov/health-it-tools-and-resources/evaluation-resources/workflow-assessment-health-it-toolkit/all-workflow-tools/potential-problem-analysis . Accessed 09 Jul 2023

43. “FAILURE MODE AND EFFECTS ANALYSIS (FMEA)”. American Society for Quality, https://asq.org/quality-resources/fmea . Accessed 09 Jul 2023

44. “Stakeholder Analysis Process”. Projectmanagement, https://www.projectmanagement.ie/blog/stakeholder-analysis-process/ . Accessed 10 Jul 2023

45. ” The Balanced Score Card”. Shree Phadnis, Master Black Belt at KPMG (India), https://www.symphonytech.com/articles/bscard.htm . Accessed 10 Jul 2023

46. “The Balanced Scorecard—Measures that Drive Performance”. Harvard Business Review, https://hbr.org/1992/01/the-balanced-scorecard-measures-that-drive-performance-2 . Accessed 10 Sep 2023

47. “MANUFACTURING DASHBOARD EXAMPLES”. Datapine, https://www.datapine.com/dashboard-examples-and-templates/manufacturing . Accessed 09 Jul 2023

48. “A comparison between Six Sigma and Lean Six Sigma”. Amileinstitute, https://www.amileinstitute.org/blog/a-comparison-between-six-sigma-and-lean-six-sigma/ . Accessed 10 Jul 2023

49. “What are the Levels (Belts) of Lean Six Sigma Certification?”. Dcmlearning, https://dcmlearning.ie/lean-resources/different-levels-belts-of-lean-six-sigma-certification.html . Accessed 11 Jul 2023

• 5S Methodology: The Ultimate Guide

Leave a Comment Cancel reply

Save my name and email in this browser for the next time I comment.

Lean Six Sigma

6 minute read

DMAIC - A Beginner's Guide

Cody Steele

Facebook Twitter LinkedIn WhatsApp Email

DMAIC definition

DMAIC is an acronym that summarizes a Lean Six Sigma methodology for solving difficult problems with existing processes. The phases provide a structure that makes success more likely. Each letter stands for a phase in the DMAIC process.

D:  D efine

M: m easure, a: a nalyze  , i: i mprove, c: c ontrol.

Want to learn more about the Lean Six Sigma methodology?

Check out this ebook that will guide you through the key concepts of LSS.

DMAIC process

The DMAIC model uses a process defined by the steps associated with each initial that makes up the acronym, as follows: 

At the beginning, you might not even have identified what problem to work on. You’ll often use DMAIC tools like Pareto analysis and Supplier-Input-Process-Output-Customer (SIPOC) diagrams to help understand which problems are leading to the biggest costs.

At the end of the define phase, you typically produce a project charter that describes elements like who will work on the problem, the project goals, and the benefits of achieving those goals. 

Define example

The following chart helps to clarify that “grinning” is the biggest problem with a painting process:

During the measure phase, you’ll want to make sure that the process that you have for measuring the process is adequate and determine the current state of the process.

You might need some of the more analytical DMAIC tools from Measurement Systems Analysis (MSA) to help decide when you are measuring well enough to understand the process to improve.

Measure example

If we do not presently measure how long it takes a medical resident to complete the required documentation of a surgical procedure for their education after the surgery, then we won’t be able to tell when the process has improved.

First, we would need to define the start and end points of the process as we’ll measure them, so that we can arrive at a measurement in days or hours.

With the problem defined and the ability to measure the process in place, you are in a suitable position to look at what might be causing the problem.

You might use a 5 Whys Analysis to refine the problem statement into a testable form. Once you have some good ideas, designed experiments can verify that a potential cause has a significant effect.

Analyze example

In a DMAIC example from a grinding process , the analyze phase is when the team determined that over 80 percent of the downtime for a machine was due to only three problems, although more than 10 problems had been considered.

During the analyze phase, your understanding of the process will have solidified so that you know what changes to make to improve the process. During the improvement phase, you’ll make sure to deliver those improvements to the full process. 

Improve example

In a DMAIC example on pumps , the analyze phase showed that operators had to hold a part too hard to keep it still, resulting in deformation of the part from three points of contact of the holding tool.

In the improvement phase, the team using the DMAIC model distributed a new tool that provided even pressure instead of pressure at three points.

Now that you’ve improved your process, it’s critical that you make those improvements part of the standard operating procedure for the process. You’ll come up with a control plan that describes the new process and you’ll implement a monitoring plan that lets you verify that the improvements are stable. 

While we generally hope that control charts at this phase show you a process that’s predictable, it’s important that the control phase also lets you know about process changes that represent opportunities for improvement. 

DMAIC diagram

The DMAIC model is often circular, as in the following DMAIC diagram:

DMAIC tools

We’ll often find that specific Lean tools are common to use at particular phases of DMAIC. The following list gives a few common tools by phase. Although tools are often most typical in particular phases, you can find uses for many tools in multiple phases. For more details on the tools in the list, go to our Lean Six Sigma tools and techniques resource.

• Failure Mode & Effects Analysis (FMEA) 
• Process Flow Charts
• Project Charter
• RACI Matrix
• Value Stream Map
• Pareto Chart
• 5 Whys Analysis
• Design of Experiments
• Fishbone Diagram
• Regression Analysis
• A3 Process/Report
• Poka Yoke (Error-Proofing)
• Total Productive Maintenance (TPM)
• Control Charts
• Standardized Work
• Statistical Process Control (SPC)

Learn more  

This resource introduced the DMAIC model with some examples and prospective tools. To learn more, try our Lean Six Sigma courses , designed to prepare you for certification with IASSC/PeopleCert. 

Prepare to get certified in Lean Six Sigma

Start learning today with GoSkills courses

Loved this? Subscribe, and join 461,231 others.

Get our latest content before everyone else. Unsubscribe whenever.

Cody is a technical communicator and statistician who wants to help people collect the right data and analyze it to make informed decisions. His specialities include statistics, technical communication, statistical reliability, JMP, SAS, and writing for translation.

Recommended

How Online Learning Can Help You Grow Professionally (and Personally)

To grow professionally doesn’t just mean climbing the corporate ladder. Explore four ways online learning fosters professional, and even personal, growth.

Process Improvement Skills Boil Down to These 3 Elements

How can you tell someone has process improvement skills? It really comes down to a combination of three important factors.

The Basics of Gage R&R

Gage Repeatability and Reproducibility studies (Gage R&R) are a type of Measurement Systems Analysis (MSA). This tutorial walks you through the basics.

© 2024 GoSkills Ltd. Skills for career advancement

🍪 This website uses cookies to improve your experience.

Learn more about our cookies Accept cookies

• Topical Articles =>
• PMP Certification
• CAPM Certification
• Agile Training
• Corporate Training
• Project Management Tools

Home / Six Sigma / The Six Sigma Approach: A Data-Driven Approach To Problem-Solving

The Six Sigma Approach: A Data-Driven Approach To Problem-Solving

If you are a project manager or an engineer, you may have heard of the  6 Sigma approach to problem-solving by now. In online Six Sigma courses that teach the Six Sigma principles , you will learn that a data-driven approach to problem-solving , or the Six Sigma approach, is a better way to approach problems. If you have a Six Sigma Green Belt certification then you will be able to turn practical problems into practical solutions using only facts and data.

Attend our 100% Online & Self-Paced Free Six Sigma Training .

This approach does not have room for gut feel or jumping to conclusions. However, if you are reading this article, you are probably still curious about the Six Sigma approach to problem-solving.

What is the Six Sigma Approach?

Let’s see what the Six Sigma approach or thinking is. As briefly described in free Six Sigma Green Belt Certification training , this approach is abbreviated as DMAIC. The DMAIC methodology of Six Sigma states that all processes can be Defined, Measured, Analyzed, Improved and Controlled . These are the phases in this approach. Collectively, it is called as DMAIC. Every Six Sigma project goes through these five stages. In the Define phase, the problem is looked at from several perspectives to identify the scope of the problem. All possible inputs in the process that may be causing the problem are compared and the critical few are identified. These inputs are Measured and Analyzed to determine whether they are the root cause of the problem. Once the root cause has been identified, the problem can be fixed or Improved. After the process has been improved, it must be controlled to ensure that the problem has been fixed in the long-term.

Check our Six Sigma Training Video

Every output (y) is a function of one or multiple inputs (x)

Any process which has inputs (X), and delivers outputs (Y) comes under the purview of the Six Sigma approach. X may represent an input, cause or problem, and Y may represent output, effect or symptom . We can say here that controlling inputs will control outputs. Because the output Y will be generated based on the inputs X.

This Six Sigma approach is called Y=f(X) thinking. It is the mechanism of the Six Sigma. Every problematic situation has to be converted into this equation. It may look difficult but it is just a new way of looking at the problem.

Please remember that the context of relating X and Y to each other would vary from situation to situation. If X is your input, then only Y becomes your output. If X is your cause, Y will not be regarded as the output. If X is your input, Y cannot be called as an effect.

Let’s go further. The equation of Y=f(X) could involve several subordinate outputs, perhaps as leading indicators of the overall “Big Y.” For example, if TAT was identified as the Big Y, the improvement team may examine leading indicators, such as Cycle Time; Lead Time as little Ys. Each subordinate Y may flow down into its own Y= f(X) relationship wherein some of the critical variables for one also may affect another little Y. That another little variable could be your potential X or critical X.

A practical vs. a statistical problem and solution

In the Six Sigma approach, the practical problem is the problem or pain area which has been persisting on your production or shop floor. You will need to c onvert this practical problem into a statistical problem. A statistical problem is the problem that is addressed with facts and data analysis methods. Just a reminder, the measurement, and analysis of a statistical problem is completed in Measure and Analyze phase of the Six Sigma approach or DMAIC.

In this approach, the statistical problem will then be converted into a statistical solution. It is the solution with a known confidence or risk levels versus an “I think” solution. This solution is not based on gut feeling. It’s a completely data-driven solution because it was found using the Six Sigma approach.

A Six Sigma approach of DMAIC project would assist you to convert your Practical Problem into Statistical Problem and then your Statistical Problem into Statistical Solution. The same project would also give you the Practical Solutions that aren’t complex and too difficult to implement. That’s how the Six Sigma approach works.

This approach may seem like a lot of work. Wouldn’t it be better to guess what the problem is and work on it from there? That would certainly be easier, but consider that randomly choosing a root cause of a problem may lead to hard work that doesn’t solve the problem permanently. You may be working to create a solution that will only fix 10% of the problem while following the Six Sigma approach will help you to identify the true root cause of the problem . Using this data-driven Six Sigma approach, you will only have to go through the problem-solving process once.

The Six Sigma approach is a truly powerful problem-solving tool. By working from a practical problem to a statistical problem, a statistical solution and finally a practical solution, you will be assured that you have identified the correct root cause of the problem which affects the quality of your products. The Six Sigma approach follows a standard approach – DMAIC – that helps the problem-solver to convert the practical problem into a practical solution based on facts and data . It’s very important to note that the Six Sigma approach is not a one-man show. Problem solving should be approached as a team with subject matter experts and decicion makers involved.

Related Posts

20 thoughts on “ the six sigma approach: a data-driven approach to problem-solving ”.

• Pingback: 5 Positions Which Must Be in a Six Sigma Team - Master of Project
• Pingback: What is the Difference Between DMAIC and DMADV in Six Sigma? - Master of Project
• Pingback: 4 Benefits of Lean Six Sigma Certification - Master of Project
• Pingback: Six Sigma: What is the Normal Distribution Curve? - Master of Project
• Pingback: How Do The Six Sigma Statistics Work? - Master of Project
• Pingback: Design for Six Sigma: Why DFSS is Important? - Master of Project
• Pingback: Defects Per Unit (DPU): The Crux Of Six Sigma - Master of Project
• Pingback: First Pass Yield vs. Roll ThroughPut Yield: Why RTY is better than FPY? - Master of Project
• Pingback: Defects per Opportunity: 5 Steps to Caluculate DPO - Master of Project
• Pingback: Sigma Level : The Most Important Statistical Term in Six Sigma - Master of Project
• Pingback: Six Sigma Certification Cost: Learn the Two Main Aspects - Master of Project
• Pingback: 5 Areas of a Project Feasibility Study in Six Sigma - Master of Project
• Pingback: 7 Elements of the Six Sigma Project Charter - Master of Project
• Pingback: 5 Key Deliverables of the DMAIC Process Measure Phase - Master of Project Academy Blog
• Pingback: 2 Types of Data for Six Sigma Measure Phase - Master of Project Academy Blog
• Pingback: Six Sigma Green Belt Certification Cost - All Aspects - Master of Project Academy Blog
• Pingback: Measures of Central Tendency - Master of Project Academy Blog
• Pingback: Understanding Discrete Probability Distribution - Master of Project Academy Blog
• Pingback: Why the Binomial Distribution is Useful for Six Sigma Projects - Master of Project Academy Blog
• Pingback: Introduction to Collecting a Sample in Statistics - Master of Project Academy Blog

Comments are closed.

Disclaimer:

• PMP, PMI, PMBOK, CAPM, ACP and PDU are registered marks of the Project Management Institute.
• ITIL® is a [registered] trade mark of AXELOS Limited, used under permission of AXELOS Limited. All rights reserved.
• PRINCE2® is a [registered] trade mark of AXELOS Limited, used under permission of AXELOS Limited. All rights reserved.
• Certified ScrumMaster® (CSM) and Certified Scrum Trainer® (CST) are registered trademarks of SCRUM ALLIANCE®
• Professional Scrum Master is a registered trademark of Scrum.org
• CISA® is a Registered Trade Mark of the Information Systems Audit and Control Association (ISACA) and the IT Governance Institute.
• CISSP® is a registered mark of The International Information Systems Security Certification Consortium ((ISC)2).

Master of Project Promo Codes PMP Articles

PMP Certification Ultimate Guide – 99.6% Pass Rate CAPM Articles

The Six Sigma Strategy's DMAIC Problem-Solving Method

• Supply Chain Management
• Sustainable Businesses
• Operations & Technology
• Market Research
• Business Law & Taxes
• Business Insurance
• Business Finance
• Becoming an Owner

Six Sigma is a business management strategy that was initially developed by Motorola in the 1980s and is used by many Fortune 500 companies today. It is primarily used to identify and rectify errors in a manufacturing or business process.

The Six Sigma system uses a number of quality methods and tools that are used by Six Sigma trained professionals within the organization. The DMAIC problem-solving method can be used to help with any issue that arises, usually by professionals in the organization who have reached the "green belt" level.

The DMAIC Method

The DMAIC problem-solving method is a roadmap that can be used for any projects or quality improvements that need to be made. The term DMAIC stands for the five main steps in the process: Define, Measure, Analyze, Improve, and Control.

• Define: It is important in Six Sigma to define the problem or project goals. The more specific the problem is defined, the greater the chance of obtaining measurements and then successfully completing the project or solving the problem. The definition should describe the issue accurately with numeric representation. For example, “damaged finished goods from the production line have increased 17 percent in the last three months." The definition of the problem or project should not be vague, such as, “quality has fallen.” As part of the definition stage, the scope of the project or issue should be defined, as well as the business processes involved.
• Measure: When the project or problem has been defined, decisions should then be made about additional measurements required to quantify the problem. For example, if the definition of the problem is “damaged finished goods from the production line have increased 17 percent in the last three months,” then additional measurements might need to be looked at. This includes what finished goods are being damaged, when they are being damaged, and the level of damage.
• Analyze: Once the measuring stage has defined the additional measurements, the data is then collected and analyzed. At this point, it is possible to determine whether the problem is valid or whether it is a random event that does not have a specific cause that can be corrected. The data that has been collected can be used as a base level to compare against measurements after the project has been completed to ascertain the success of the project.
• Improve: After measurements have been taken and analyzed, possible solutions can then be developed. Test data can be created and pilot studies launched to find which of the solutions offers the best improvements to the issue. The team should also look at the results to ensure that there are no unanticipated consequences to the selected solution. When the most appropriate solution is selected, then the team can develop an implementation plan and a timeline for the completion of the project.
• Control: After the implementation of the solution or project, a number of controls must be put in place so that measurements can be taken to confirm that the solution is still valid and to prevent a recurrence. The control measurements can be scheduled for specific dates, e.g., monthly, daily, and yearly. The solution should also be well documented and any other related process documentation updated.

The DMAIC problem-solving method can produce significant improvements for an organization that is using the Six Sigma methodology and tools. The method offers a five-step plan that gives organizations a roadmap to follow so that issues can be resolved using a structured methodology.

• The Living Supply Chain Glossary
• The Origins and Principles of Lean Manufacturing
• 7 Ways To Optimize Your End-to-End Supply Chain
• Wholesaling Distribution Channels
• 7 Warehouse Pallet Storage Methods
• Introduction to Lawson ERP Software
• 6 Ways to Know Your Wholesale Target Market
• Reorder Methodologies in Manufacturing
• Order Picking in the Warehouse
• The Top 9 Reasons You Do Not Have 100% Inventory Accuracy
• Contract Termination
• Cycle Counting in the Warehouse
• Small Business Guide to Manufacturing
• Strategic Forecasting In The Supply Chain For Manufacturers
• Efficient Packaging Methods in a Warehouse
• Department of Transportation Truck Inspections

• Insights & Resources

What Is Six Sigma?

Six Sigma is a problem solving methodology rooted in data. Born at Motorola in 1986, the approach quickly gained recognition among global corporations thanks to Jack Welch at GE.

Today, Six Sigma is applied across organizations, large and small, and is heralded for its rigorous, data-driven approach to improving process performance and instilling continuous improvement.

Six Sigma is more than simply a set of tools; it is a methodology that brings a roadmap, roles, language and culture change to an organization. It is about identifying your biggest problems, assigning them to your best people, and providing the resources and support to solve those problems—once and for all.

What Does “Six Sigma” Mean?

Number of defects stratified by sigma level

The goal of Six Sigma is an aggressive one. It translates to only 3.4 defects per million opportunities (DPMO). In a six sigma process, 99.99966% of the opportunities—defined based on those critical elements important to your customers—are defect-free.

When considering defects and opportunities, it’s important to define them through the eyes of your customer. Rather than counting every possible opportunity for an error, you want to count the ones that are most important.

Six Sigma is about improving customer satisfaction, and to do so means understanding what matters to your customers. Once you can link customer satisfaction to internal business processes, you can appropriately drive improvements in the business.

The DMAIC Roadmap

The heart of the Six Sigma methodology is the DMAIC roadmap, which combines sound problem solving methods with proven tools. DMAIC stands for Define-Measure-Analyze-Improve-Control.

One of the goals in a DMAIC project is to identify the most significant variables, or X’s, affecting the outputs, or Y’s, of the process you’re concerned with. This is characterized by a simple equation: Y = f(X). If we understand the relationship between X’s and Y’s, where the X’s are the customer’s needs, and the Y’s are the owner’s needs, we can directly measure those things that keep us in touch with our customers.

Goals in a DMAIC project are to identify the most significant variables affecting the outputs of the process you’re concerned with and to ensure that a problem is never going to come back.

Another goal of a DMAIC project is to ensure that a problem is never going to come back, because we’re finally going to get an intimate understanding of the way our process works.

There’s a well-supported rule of thumb, the Pareto Principle , which states that 80 percent of the effects in any process are caused by 20 percent of the causes. Also known as the law of the vital few, with these critical input variables properly identified, we can put systems in place to ensure that improvements are maintained for the long-term.

Roles and Responsibilities

Within a Six Sigma deployment or effort, there are a handful of important roles. Here’s an overview of those roles and the responsibility and associated training of each.

Executives & Deployment Leaders

Key leaders of the culture change, executives and deployment leaders own the vision, direction, integration and results of a Six Sigma program. They’re responsible for determining the scope of a deployment, and identifying goals and strategic priorities that Champions will use to align projects.

Six Sigma Core Team

The core team is a group of multidisciplinary business leaders from key supporting functions of the company: finance, human resources, information technology, communications, training, and operations. They are responsible for taking the vision of the executive team and making it a reality. They help create the supporting infrastructure that enables the long-term success of Black Belts and other performance excellence leaders. Of this group, the finance representative plays a particularly important role in assisting with forecasting for potential projects and validating and tracking project savings.

Master Black Belt

Master Black Belts are gurus of the process excellence world. They’re highly respected and sought-after resources who not only wield considerable knowledge of problem solving methodologies, but also coach and mentor other professional problem solvers, including Green Belts and Black Belts. Master Black Belts take more of a strategic role in the organization both in selecting tactical projects needed to achieve strategic goals and in developing future leaders that will eventually manage and lead the business. They also manage the project pipeline, develop and administer curriculum, support the deployment leader and champions, and lead large-scale projects. Training: Master Black Belt Development Program

Black Belt certification is seen as a personal and professional development building block.

Black Belts

Black Belts are key resources of a Six Sigma program who are 100 percent dedicated to the effort. They facilitate and lead projects, provide deployment support, and coach and train other performance excellence resources. As dedicated resources that complete four to six projects a year, Black Belts experience a 7:1 ROI and average $200,000 in median savings per project . Additionally, Black Belt certification is seen as a personal and professional development building block that prepares people for leadership roles later on. Training: Black Belt | Black Belt Online | Green Belt to Black Belt Upgrade | GB to BB Upgrade Online

Green Belts

Green Belts carry the language of Six Sigma deeper into the organization. These part-time resources implement smaller scale projects that have direct impact to daily non-Six Sigma duties. They are skilled in the DMAIC methodology and principles of Six Sigma, and assist Black Belts with team activities and tool application. They become local advocates, supporting improvement efforts through data-driven decision-making and accelerate the number of employees positively affected by Six Sigma. Training: Green Belt | Green Belt Online

Process Owners

As the Process Owner, this team member owns the solution delivered by the Six Sigma team and is responsible for its implementation. The Process Owner assists with culture change at a local level, as well as with project identification and providing resources to serve as team members on projects. The Process Owner may also be involved in scoping and defining projects and providing support to the project team. Training: Yellow Belt Online

Team Members

Providing invaluable process expertise, Team Members assist Black Belts with data collection and tool application. They also assist the Process Owner with the long-term implementation of the solution and extend the reach of the Six Sigma language into the trenches. Training: Yellow Belt Online

Complementary Methods

While some companies deploy Six Sigma solo, more often than not it is part of broader continuous improvement or performance excellence efforts that include Lean , innovation , and other problem solving approaches.

Six Sigma is often applied in conjunction with Lean. Lean focuses on reducing waste so what is left is value-added. Six Sigma focuses on reducing variation and defects. Together, the two become a powerful combo to first lean out and then perfect your processes. In the last decade, companies have moved from treating Lean and Six Sigma as independent approaches to combining them into an improved operating system.

All of these continuous improvement efforts roll up into the organization’s strategic planning and execution , ensuring that everyone is working on improvements and innovations that align with the company’s strategic goals.

• Product overview
• All features
• Latest feature release
• App integrations

CAPABILITIES

• project icon Project management
• Project views
• Custom fields
• Status updates
• goal icon Goals and reporting
• Reporting dashboards
• workflow icon Workflows and automation
• portfolio icon Resource management
• Capacity planning
• Time tracking
• my-task icon Admin and security
• Admin console
• asana-intelligence icon Asana AI
• list icon Personal
• premium icon Starter
• briefcase icon Advanced
• Goal management
• Organizational planning
• Campaign management
• Creative production
• Content calendars
• Marketing strategic planning
• Resource planning
• Project intake
• Product launches
• Employee onboarding
• View all uses arrow-right icon
• Project plans
• Team goals & objectives
• Team continuity
• Meeting agenda
• View all templates arrow-right icon
• Work management resources Discover best practices, watch webinars, get insights
• Customer stories See how the world's best organizations drive work innovation with Asana
• Help Center Get lots of tips, tricks, and advice to get the most from Asana
• Asana Academy Sign up for interactive courses and webinars to learn Asana
• Developers Learn more about building apps on the Asana platform
• Community programs Connect with and learn from Asana customers around the world
• Events Find out about upcoming events near you
• Partners Learn more about our partner programs
• Asana for nonprofits Get more information on our nonprofit discount program, and apply.

Featured Reads

• Project management |
• Six Sigma: All you need to know about t ...

Six Sigma: All you need to know about the lean methodology

Six Sigma is a process improvement method that helps organizations improve their business processes. The end goal of Six Sigma is to reduce the amount of variations in a process as much as possible in order to prevent defects within your product. While this methodology is often used to optimize manufacturing processes, it can also be applied to other industries—including tech companies who produce digital products rather than physical ones.

Imagine your development team is in the process of putting the final touches together for a big product launch. When the product gets to the testing stage, the team catches several unanticipated bugs in the code. How can your team prevent this from happening in the future?

One way to do this is to implement an old manufacturing tool: the Six Sigma methodology.

What is Six Sigma?

The main philosophy of Six Sigma is that all processes can be defined, measured, analyzed, improved, and controlled (commonly referred to as the DMAIC method).

According to Six Sigma, all processes require inputs and outputs. Inputs are the actions that your team performs, and the outputs are the effects of those actions. The main idea is that if you can control as many inputs (or actions) as possible, you also control the outputs. 

Where does Six Sigma come from?

In 1809 , German mathematician Carl Friedrich Gauss first used the famous bell curve to explain measurement errors. In the 1920s , Walter Shewhart found that three sigma from the mean is the precise point where a process needs to be corrected. 

But it wasn’t until 1986 that the engineer and developer Bill Smith created the Six Sigma methodology for Motorola that we know today. Motorola used the methodology to identify the maturity of a process by its “sigma” rating, which indicates the percentage of products that are defect-free.

By definition, a Six Sigma process is one in which fewer than 3.4 defects per million opportunities occur. In other words, 99.9997% of opportunities are statistically expected to be free of defects.

Six Sigma is still commonly used in lean manufacturing and production because the process can be helpful in preventing and eliminating defects. However, this methodology can also be used in the service industry and with software engineering teams.

Lean Six Sigma

In general, the goal of a lean methodology is to drive out waste or anything that doesn’t add value to a product or process. The Lean Six Sigma (LSS) methodology values defect prevention over defect detection. This means that the goal of LSS is not to identify where the defect is, but to prevent defects from happening in the first place. 

The 5 key principles of Six Sigma

The Six Sigma methodology has five key principles you can use when analyzing your processes.

1. Focus on the customer

In Six Sigma, the goal is to ensure you can provide your customers with as much value as possible. This means your team should spend a lot of time identifying who your customers are, what their needs are, and what drives their behavior to purchase products. This principle works well for SaaS companies since they often focus on recurring revenue streams.

Identifying your customer’s wants and needs can help your team better understand how to retain customers and keep them coming back to your product.

This requires your team to understand the quality of product your customers would find acceptable, so you can meet or even exceed their expectations. Once you understand that level of quality, you can use it as a benchmark for production. 

2. Use data to find where variation occurs

Outline all of the steps of your current production process. Once you’ve done this, analyze and gather data on the current process to see if there are certain areas that can be optimized or areas that are causing a bottleneck in your workflow.

For example, consider how you share information with your team. Is everyone on your team getting the same information, or are they referencing outdated documents? Establishing a centralized location for all pertinent project information can help minimize the amount of time spent searching for the right documents.

Sometimes it can be challenging to decide what metrics you need to analyze. An easy way to figure this out is by working backward. Identify a goal you want to achieve and work back from there. For example, if your goal is to shorten production time, analyze how long each step in the production process takes.

3. Continuously improve your process

While you’re looking at your production process, consider any steps that don’t add value for your team or your end customers. Use tools such as value stream mapping to identify where you can streamline processes and decrease the amount of bottlenecks. 

The idea of making small improvements to your processes over time is known as kaizen , or continuous improvement. The philosophy behind continuous improvement is that if you’re making small changes over a long period of time, it can lead to major positive changes in the long run.

4. Get everyone involved

Six Sigma is a methodology that allows everyone on the team to contribute. However, this does require everyone on the team to have some training on the Six Sigma process to reduce the risk of creating more blockers instead of getting rid of them. 

Six Sigma works especially well when cross-functional teams are involved, because it provides a holistic view of how a process can affect all parts of your business. When you include representatives from all teams involved in a process, you give everyone insight into the improvements you’re making and how those changes might impact their teams.

We’ll dive into the different types of Six Sigma trainings and certifications later in this article.

5. Ensure a flexible and responsive ecosystem

Six Sigma is all about creating positive change for your customers. This means you should consistently look for ways to improve your processes, and your entire team should stay flexible so they can pivot without much disturbance.

This also means that processes need to be easily interchangeable. An easy way to do this is to break out processes into steps. If there’s an issue with just one step, then only that step needs to be fixed, as opposed to the entire process. 

The two main Six Sigma methodologies

There are two common processes within Six Sigma and they’re each used in different situations.

In general, the DMAIC method is the standard method to optimize existing processes. Alternatively, use the DMADV method when a process is not yet established and you need to create one.

DMAIC is an acronym, meaning each letter represents a step in the process. DMAIC stands for define, measure, analyze, improve, and control.

Define the system. Identify your ideal customer profile, including your customers’ wants and needs. During this stage you also want to identify the goals of your entire project as a whole.

Measure key aspects of current processes. Using the goals you established in the “define” stage, benchmark your current processes and use that data to inform how you want to optimize your project.

Analyze the process. Determine any root causes of problems and identify how variations are formed.

Improve or optimize your process. Based on the analysis from the previous step, create a new future state process. This means you should create a sample of the improved process and test it in a separate environment to see how it performs.

Control the future state process. If the results in the “improve” stage are up to your team’s standards, implement this new process into your current workflow. When doing this, it’s important to try and control as many variables as possible. This is often done using statistical process control or continuous monitoring.

DMAIC example

Your product team notices that the customer churn rate (the rate at which customers stop doing business with you) is increasing. To prevent this problem from getting worse, you can use the Six Sigma DMAIC methodology to identify the issue and develop a solution. 

Define: The customer churn rate has increased from 3% to 7% in the last six months.

Measure: Your team has a lot of information about how prospective customers convert into actual customers, but there’s not much information about what happens after someone becomes a customer. You decide to analyze and measure user behavior after they purchase the product.

Analyze: After looking at the behavior of users after they become customers, your team notices that newer customers are having a harder time getting used to the new product UI than existing customers.

Improve: Your team decides to implement a “new customer onboarding” workflow that helps customers identify key parts of the product and how to use it. Your team works with the customer success team to help set best practices and create trainings. This gives the customer success team all the information they need to train new customers effectively and ensure customer satisfaction. 

Control: Your team monitors both the churn rate and how customers are behaving now that the changes have been implemented. After a few months, you notice the churn rate beginning to decrease again, so you choose to keep the new changes to the process.

The DMADV method is sometimes referred to as Design for Six Sigma (DFSS). DMADV stands for define, measure, analyze, design, and verify. Here’s what to do during each phase:

Define your goals. When defining goals for the new process you’re establishing, it’s important to consider both business goals and the goals of your ideal customer profile. 

Measure and identify CTQs. CTQ stands for “critical to quality.” These are the characteristics that define your perfect product. During this step you will identify how your new process can help achieve these CTQs and any potential risks that could impact quality.

Analyze to develop and design multiple options. When you’re designing a new production process, it’s important to have multiple options. Take a look at the different options you create and analyze the strengths and weaknesses of each one. 

Design the chosen option. Based on the analysis in the previous step, take the next step and implement the option that best fits your needs. 

Verify the design and set up pilot runs. Once you finish implementing your process, it’s time to hand it over to process owners and measure how the process works. Once the process is up and running, then your team can optimize it using the DMAIC method. 

Six Sigma certification

Six Sigma is a multi-level training program . Much like in martial arts, each ranking is a different belt color that indicates a different body of knowledge and years of experience. The Six Sigma certification program breaks down into six different rankings—from white belt to champion:

White Belt : If you’re brand-new to the Six Sigma method, you’ll start out in this stage. Someone with a Six Sigma White Belt doesn’t need to have any formal training or certification in Six Sigma, but they understand the basic framework and guidelines. This means they can participate in waste reduction and quality control projects. 

Yellow Belt : This level requires some formal training and you can receive an official Six Sigma Yellow Belt certification. With a Yellow Belt you can help contribute to strategy more than you could with a White Belt. You can now assist higher-ups with problem solving and analysis.

Green Belt : With a Six Sigma Green Belt certification, you can start strategizing and implementing smaller process improvement techniques on your own.

Black Belt : Once you receive the Black Belt certification, you will be able to break down processes and handle more complex projects than any previous belts. In this training, you’re taught how to manage large-scale changes that can impact a business’s bottom line.

Master Black Belt : The Six Sigma Master Black Belt is an additional course that helps you enhance your current skills by deepening your understanding of Lean Six Sigma. You’ll learn more about statistical tools and cultivate a greater appreciation for the DMAIC method.

Champion : You can become a Six Sigma Champion with a final training that is typically helpful for senior managers and executives who want to become proficient in guiding project teams and leaders through the different DMAIC phases. 

While there is no unified standard for certification, the courses are designed to teach the essentials of the process and how to apply Six Sigma tools to your day-to-day work situations.

Track and improve workflows with Six Sigma

Improving your business processes ultimately helps reduce waste. As you brainstorm and analyze workflows, take time to pinpoint and address bottlenecks . Visualize each step in your production process so you can assign them to specific owners.

If you’re looking to improve your team’s workflows , it’s best to use software that helps connect your team and manage goals. Asana workflows can help you manage and automate how work is completed. Plus, you can easily alert other team members of workflow changes, make real-time adjustments, and create a single source of truth for your entire team.

Related resources

New site openings: How to reduce costs and delays

8 steps to write an effective project status report

Provider onboarding software: Simplify your hiring process

Inventory management software: How to control your stock

Six Sigma Fundamentals: What is DMAIC?

Six Sigma and DMAIC

If the Six Sigma quality improvement methodology had to be summarized in one word, it would be the acronym DMAIC. This shorthand description lists the steps of the Six Sigma process when improving existing business processes. It provides an overview of the method by which Six Sigma projects are completed, namely: define, measure, analyze, improve and control.

What is DMAIC?

Process is the focal point of DMAIC. The methodology seeks to improve the quality of a product or service by concentrating not on the output but on the process that created the output. The idea is that concentrating on processes leads to more effective and permanent solutions.

When to Use DMAIC

DMAIC is used by a project team that is attempting to improve an existing process. DMAIC provides structure because each phase of the process contains tasks and tools that will lead the team to find an eventual solution. While DMAIC may be sequential, it is not strictly linear. The process encourages project teams to backtrack to previous steps if more information is needed.

The phases of DMAIC

The phases or stages of DMAIC include:

Define – The project begins by creating a team charter to identify team members, select the process the team will be improving and clearly define the objective of the project. The project team will then identify the CTQs to help measure the impact the problem has on the customer. This phase is completed when the team creates a process map that includes the process’s inputs and outputs .

Measure – This phase includes creating and executing a data collection plan that provides reliable and significant data. The data indicates how the process is performing and helps identify the villain in the Six Sigma narrative – variance. After this point, the project team’s efforts focus on eliminating or reducing variance as much as possible.

Analyze – Once process performance has been quantified, the analyze phase of DMAIC helps identify possible causes of the problems. A sub-process map can help identify the problems in the process and tools such as ANOVA and regression analysis can help narrow these problems to root causes. In this phase, the team is able to quantify the financial benefit of solving the problem.

Improve – Once the problem’s root cause is brought to light, the improve phase focuses on finding a permanent solution to the problem. This is where the project team’s creativity comes into play in finding an answer to a longstanding process problem. The team then tests a proposed solution in a pilot program to test if the solution is effective and financially viable.

Control – In this phase, the project team documents the new solution that they have created so that it can be passed on to process owners. The project team then implements the solution according to the timeline and key milestones they have developed. Once the solution has been implemented, the project team monitors it for several months and if it meets performance expectations turns it over to the process owner .

DMAIC is a systematic, objective and fact-based system of problem solving. The steps in the Six Sigma DMAIC methodology make process improvement accessible and learnable even for those who are just becoming acquainted with it.

DMAIC Roadmap - Click to View

Together, the Lean Six Sigma Problem Solving and the DMAIC Methodology have successfully existed over the last 50 years. It is a proven approach that combines the principles of Lean and Six Sigma to optimize processes, reduce defects, and achieve operational excellence. And, it is critical to note, that the methodology of DMAIC (Define, Measure, Analyze, Improve, Control), which is the core of Lean Six Sigma, is why Lean Six Sigma remains highly valued today. Let's explore how DMAIC enables you to solve problems efficiently, enhance productivity, and deliver exceptional results. Join me on this brief journey as I outline how D.M.A.I.C. is the core of Lean Six Sigma Problem Solving.

Understanding Lean Six Sigma Problem Solving and DMAIC

Lean Six Sigma is a methodology designed to improve operational efficiency, reduce waste, and enhance overall quality. It embraces a fact-based, data-driven approach and provides organizations with a structured framework to identify and address issues effectively. That framework is the DMAIC methodology. It's a well-defined project management approach to discovering the Y=f(x) equation, where the "Y" is the measure of that thing you're trying to improve, and the "x's" are "influencing" (good or bad) that "Y's" output.

Define Phase

The first step in every Lean Six Sigma Problem Solving effort is to define the problem and the goal. It's no different than looking at a map before a road trip with your friends. You can map your route if you know..

• Where you are
• Where you're going.

If you don't know either of those, you'll be driving around aimlessly. Of course, there are several other important elements to the define phase and certainly the entire DMAIC process. However, without a quantifiably defined problem and goal.. your efforts will be fruitless.

Measure Phase

Once the problem is defined and the goal is set, you have the "Y" part of the "Y"=f(x) equation. It's time to put several things in motion.

• Begin measuring your "Y" over time and as frequently as necessary.
• Brainstorm all the potential "x's" influencing the "Y"
• Prioritize the potential "x's"
• Begin measuring the "x's" in such a way that you can correlate them to your "Y"

Analyze Phase

If you're following this process in your project, then it's time to start using all the data you've been collecting. The intent of the Analyze phase is to "determine the root cause", but, to do so with data! Not conjecture. In Analyze, you should be focused on facts, data, and input from subject matter experts. Your focus will be:

• Eliminate insignificant "x's"
• Validate significant "x's"

If it sounds easy.. it's not. It's always complicated, and oftentimes, you'll discover that there are inputs to the "x's" that require measurement and analysis. It's not a linear process, it's iterative. But if the steps are followed and repeated as necessary.. you'll get there.

Improve Phase

The expectation in a DMAIC or "Lean Six Sigma Problem Solving" project is that when you think you've determined the root cause(s) that most significantly influence your "Y," you then need to prove it, and/or implement it. So now, with a clear understanding of the problem and its root causes, the Improve phase focuses on generating and evaluating potential solutions. Engaging cross-functional teams to collaborate and brainstorm ideas, pilot-test proposed improvements, and implement changes. Continuous data monitoring, process and SME feedback, and iteration ensure solutions will align with the desired result of your "Y" output. Improve is where as a Lean Six Sigma practitioner you'll be called upon to demonstrate advanced facilitation, communication, and project management skills.

Control Phase

Once solutions are implemented, the control phase ensures the improvements are sustained over time. You'll develop control plans to monitor and measure process performance, establish standard operating procedures, and provide ongoing training. By maintaining control, you can prevent regression and ensure continuous improvement in the long run. Control involves monitoring critical "x's" over time and managing them to yield expected results from your "Y." It requires people to be accountable, action plans and re-action plans to be in place, mitigation plans, communication & notification plans , training plans, etc. The control phase is as critical as the others but is often overlooked. Be sure to put sustainable plans in place to maintain your improvements.

Using Lean Six Sigma Problem Solving and DMAIC

While the structure of the D.M.A.I.C. methodology is simple and logical, the sheer volume of information, tools, techniques, templates, and data analysis that it contains suggests it's not simple. Yet, each tool or technique is fairly simple and amazingly effective when used timely and appropriately. It's the Lean Six Sigma Black Belt's job to know as much and as many tools, and techniques as possible so that he or she is prepared to face the problems, issues, roadblocks, and opportunities that reveal themselves throughout a Lean Six Sigma project. This is why a Lean Six Sigma Black Belt commands a six-figure salary. The knowledge and skills acquired through a Lean Six Sigma Black Belt Certification can be a major career booster.

Lean Six Sigma Problem Solving and the D.M.A.I.C. methodology provide organizations with a systematic and data-driven approach to address challenges, enhance productivity, and achieve operational excellence. By learning and embracing DMAIC and all the tools and techniques it embodies, organizations will look to you for leadership, expertise, and results. And you, in turn, can push forth continually learning and advancing your career.

Lean Six Sigma Certification Options

Yellow belt certification.

Green Belt Certification

Black Belt Certification

About Michael Parker

Michael Parker is the founder and president of Lean Sigma Corporation, a leading Lean Six Sigma certification provider, and licensor of premium training content to universities and corporations world wide. Michael has over 25 years of experience leading and executing Lean Six Sigma programs and projects. As a Fortune 50 senior executive, Michael led oversight of project portfolios as large as 150 concurrent projects exceeding $100 million in annual capital expenditures. Michael has also managed multi-site operations with the accountability of over 250 quality assurance managers, analysts, and consultants. He is an economist by education, earning his Bachelor of Science degree from Radford University while also lettering four years as an NCAA Division I scholarship athlete. Michael earned his Six Sigma Master Black Belt certification from Bank of America and his Black Belt certification from R.R. Donnelley & Sons. He holds nine U.S. Copyrights for his "Learn Six Sigma" publications, and a U.S. Patent.

Remember Me

Six Sigma DMAIC Roadmap

Published: March 12, 2010 by iSixSigma-Editorial

The Six Sigma DMAIC (Define, Measure, Analyze, Improve, Control) methodology can be thought of as a roadmap for problem solving and product/process improvement.

Most companies begin implementing Six Sigma using the DMAIC methodology, and later add the DFSS (Design for Six Sigma, also known as DMADV or IDDOV) methodologies when the organizational culture and experience level permits. You can read the main differences between DMAIC and DMADV , but we’ll focus on the DMAIC in this article.

While the DMAIC methodology presented above in the graphic and below in the listing may appear linear and explicitly defined, it should be noted that an iterative approach may be necessary – especially for Black Belts and Green Belts that are new to the tools and techniques that make up DMAIC. For instance, you may find that upon analyzing your data (Analyze phase) you did not gather enough data to isolate the root cause of the problem. At this point, you may iterate back to the Measure phase.

In addition, prior knowledge of the tools and techniques is necessary in determining which tools are useful in each phase. Remember, the appropriate application of tools becomes more critical for effectiveness than correctness, and you don’t need to use all the tools all the time.

As you can see, the power of the Six Sigma DMAIC methodology lies in the structure and the rigor. Of the hundreds of TQM tools that have been developed over the years, the most important ones (described above) are taught in detail by consultants to Black Belts and Master Black Belts.

About the Author

iSixSigma-Editorial

Failure Analysis of Automotive Drive System: A Six Sigma DMADV Approach

• Tools and Techniques
• Published: 24 August 2024

Cite this article

• Shivagond Teli 1 ,
• Vinod Surange   ORCID: orcid.org/0000-0002-3388-9489 2 &
• Lokpriya Gaikwad 3  

Explore all metrics

This study outlines the application of the Six Sigma methodology to rectify oil seal leaks in an automobile company's hollow drive shafts. Persistent issues with oil seepage through the shaft's oil seal led to clutch malfunctions, power failures, and subsequent breakdowns, resulting in high warranty costs, which negatively impacted the status of a firm in the market and the level of fulfillment experienced by its clients. Projects are crucial for translating an organization's strategic goals into achievable outcomes, serving as the cornerstone of success. We implemented a quality-driven effort using Six Sigma and the Theory of Inventive Problem Solving (TRIZ) to foster a culture of continuous improvement. Utilizing the procedures-oriented DMADV (Define, Measure, Analyze, Design, and Verify) technique, the oil seal leakage issue was addressed and resolved successfully from the gearbox. The Pugh matrix was used to choose a new design from various alternatives, a KANO model to evaluate customer demands, and a cause-and-effect diagram to analyze possible failure situations. The overall aim was to determine the failure situations that were most likely to occur. Through its deployment, we intended to improve both the product's dependability and the production process's efficiency. Following the design improvements, the defects observed in the assemblies dropped to 58, with no occurrences of oil seal leakage. It is plausible to conclude that these techniques can significantly enhance product quality. The study demonstrates the efficacy of Six Sigma methodologies in tackling intricate situations.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save.

• Get 10 units per month
• Download Article/Chapter or eBook
• 1 Unit = 1 Article or 1 Chapter
• Cancel anytime

Price includes VAT (Russian Federation)

Instant access to the full article PDF.

Rent this article via DeepDyve

Institutional subscriptions

Similar content being viewed by others

Application of 7-Step Problem-Solving Methodology for Defect Elimination: A Case Study in an Automotive Industry

Advanced RCM Industry Case—Modeling and Advanced Analytics (ELMAS) for Improved Availability and Cost-Efficiency

Integrating Reliability, Availability, and Maintainability Issues for Analyzing Failures in Fuel Injection Pump

Explore related subjects.

• Artificial Intelligence

S. Thawani, Six Sigma—strategy for organizational excellence. Total Qual. Manag. Bus. Excell. 15 (5–6), 655–664 (2004). https://doi.org/10.1080/14783360410001680143

Article   Google Scholar  

S.D.R. Perera, Failure on an automobile rear axle shaft. J. Fail. Anal. Prev. 22 (3), 934–939 (2022). https://doi.org/10.1007/s11668-022-01412-x

I. Daniyan, A. Adeodu, K. Mpofu, R. Maladzhi, M.G. Kana-Kana Katumba, Application of lean Six Sigma methodology using DMAIC approach for the improvement of bogie assembly process in the railcar industry. Heliyon. 8 (3), e09043 (2022). https://doi.org/10.1016/j.heliyon.2022.e09043

Article   PubMed   PubMed Central   Google Scholar  

L.M. Gaikwad, S.N. Teli, V.S. Majali, U.M. Bhushi, An application of Six Sigma to reduce supplier quality cost. J. Inst. Eng. Ser. C. 97 (1), 93–107 (2016). https://doi.org/10.1007/s40032-015-0200-2

M. Singh, R. Rathi, Investigation of critical success factors associated with Lean Six Sigma implementation in MSMEs using best worst method. Int. J. Six Sigma Compet. Advant. 12 (2/3), 209–233 (2020). https://doi.org/10.1504/IJSSCA.2020.110976

K.M. Suresh, P. Asokan, S. Vinodh, Application of design for Six Sigma methodology to an automotive component. Int. J. Six Sigma Compet. Advant. 10 (1), 1–23 (2016). https://doi.org/10.1504/IJSSCA.2016.080446

D.S. Jiju Antony, J.J. Dahlgaard, Lean Six Sigma and innovation: an exploratory study among UK organisations. Total Qual. Manag. Bus. Excell. 27 (1–2), 124–140 (2016). https://doi.org/10.1080/14783363.2014.959255

V.G. Surange, Implementation of Six Sigma to reduce cost of quality: a case study of automobile sector. J. Fail. Anal. Prev. 15 (2), 282–294 (2015). https://doi.org/10.1007/s11668-015-9927-6

L.M. Gaikwad, U. Bhushi, S.N. Teli, Implementation of Six Sigma methodologies to gain a competitive advantage: a case study approach (2022). https://doi.org/10.1109/ASET53988.2022.9735103

A. Trubetskaya, O. McDermott, P. Durand, D.J. Powell, Improving value chain data lifecycle management utilising design for Lean Six Sigma methods. TQM J. 36 (9), 136–154 (2024). https://doi.org/10.1108/TQM-01-2024-0020

S.G. Bidikar, S.B. Rane, P.R. Potdar, Product development using design for Six Sigma approach: case study in switchgear industry. Int. J. Syst. Assur. Eng. Manag. 13 (1), 203–230 (2022). https://doi.org/10.1007/s13198-021-01199-4

F.-K. Wang, C.-T. Yeh, T.-P. Chu, Using the design for Six Sigma approach with TRIZ for new product development. Comput. Ind. Eng. 98 , 522–530 (2016). https://doi.org/10.1016/j.cie.2016.06.014

D.M. Wu, C.K.P. Luk, W.Z. Fei, Quality control of low-cost electric machines for electric vehicles by DOE assisted six sigma DMADV method, in 2017 7th International Conference on Power Electronics Systems and Applications: Smart Mobility, Power Transfer & Security (PESA) (2017), pp. 1–8. https://doi.org/10.1109/PESA.2017.8277740

K. Guler, D.M. Petrisor, A Pugh Matrix based product development model for increased small design team efficiency. Cogent Eng. 8 (1), 1923383 (2021). https://doi.org/10.1080/23311916.2021.1923383

Download references

Author information

Authors and affiliations.

Bharati Vidyapeeth College of Engineering, Navi Mumbai, India

Shivagond Teli

Symbiosis Institute of Business Management, Nagpur, Symbiosis International (Deemed University), Pune, India

Vinod Surange

SIES Graduate School of Technology, Navi Mumbai, India

Lokpriya Gaikwad

You can also search for this author in PubMed   Google Scholar

Corresponding author

Correspondence to Vinod Surange .

Additional information

Publisher's note.

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Teli, S., Surange, V. & Gaikwad, L. Failure Analysis of Automotive Drive System: A Six Sigma DMADV Approach. J Fail. Anal. and Preven. (2024). https://doi.org/10.1007/s11668-024-02003-8

Download citation

Received : 21 March 2024

Revised : 06 July 2024

Accepted : 21 July 2024

Published : 24 August 2024

DOI : https://doi.org/10.1007/s11668-024-02003-8

Share this article

Anyone you share the following link with will be able to read this content:

Sorry, a shareable link is not currently available for this article.

Provided by the Springer Nature SharedIt content-sharing initiative

• Automotive manufacturing
• TRIZ methodology
• Critical-to-Quality (CTQ)
• Find a journal
• Publish with us
• Track your research