During my Six Sigma training sessions, frequently I come across some questions from participants-

How should we start six sigma project in our organization?

When should we start six sigma project in our organization?

Do we wait for any customer complaint or any outside view about process issues?

Is six sigma really applicable, as we don’t observe sầu any process defect?

The philosophy behind six sigma approach is:

Whatever we measure; acquires our focus

Whatever we focus; leads lớn improvement

Hence, identify critical success factors for your business process. Define process metrics to lớn measure process performance. With six sigma methodology, you can improve this process performance. Six sigma is a logical structured approach to improve business processes.

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The Greek letter “Sigma” a statistical term; measures how much a given process deviates from perfection. Sigma is also known as standard deviation of the process from its mean. Six Sigma process enables an organization to lớn measure the number of “defects” in a process, methods to eliminate them and get cchiến bại to “zero defects” as much as possible.

Managers face challenges in improving the quality và efficiency of the business. To overcome, they need khổng lồ implement the best methodology and tools khổng lồ analyze and control the process. The best way khổng lồ improve sầu the result is lớn improve sầu the process.

What is Six Sigma?

Let’s understand Six Sigma to get better clarity on this method.

Six Sigma is a measurement-based strategy for process improvement. It’s a methodology, which aims at improving process & increasing customer satisfaction (Both internal & external). The concept behind this approach is lớn reduce the variation in processes. This reduction leads khổng lồ consistent & desired outcomes from processes. Hence, Continuous process improvement with low defects is the goal of this method.

Six Sigma Model (DMAIC Model) for process unique improvement:

Six Sigma follows the DMAIC Mã Sản Phẩm for chất lượng improvement and problem reduction (For existing processes). This well-defined process approach consists of five sầu phases in order:

Image Source: http://businesscherub.comFigure 1: Understanding DMAIC






It is an integral part of Lean Six Sigma process, but can be implemented as a standalone quality improvement process. Indeed, it is the most preferred tool that can help improving the efficiency and the effectiveness of any organization. Within the DMAIC framework, Six Sigma can utilize several quality management tools.

Seven Basic Quality Tools (Quality core tools):

Below is the menu of some quality management tools, popularly known as seven basic chất lượng tools –

Cause & effect diagram or Ishikawa diagram

Flow Chart

Pareto Chart


Cheông chồng Sheet

Scatter Plot

Control Chart

These basic tools are helpful in six sigma projects at different times.

Now, let"s discuss them to get better clarity và understanding:

1. Cause & Effect Diagram:

Also, known as Fishbone diagram. Attributed lớn Kaoru Ishikawa, the diagram has its shape similar khổng lồ a fish skeleton. Hence, named as Fishbone diagram. This tool is used lớn explore causes lớn a single effect (or event) through brainstorming. These causes are put under different comtháng categories known as 5 M or 6 M. Where, 6 M expands as – Man, Material, Method, Machine, Measurement & Mother Nature.

2. Flow Chart:

It suggests the process flow in a diagrammatic way. Outlines a pictorial representation of processes or process steps to understand their flow upstream or downstream.

3. Pareto lớn Chart:

Also, known as 80:trăng tròn principle. Attributed khổng lồ Vilfrevì Parekhổng lồ, Principle states, 80% of the outcome is a result of 20% causes. It’s a kind of bar chart showing the frequencies of different causes or factors in descending order. The main purpose of this chart is to highlight the most significant factors ahy vọng a number of factors.

4. Histogram:

It’s a bar chart lớn study the frequency distribution of data phối. It’s used lớn underst& nature of data.

5. Checksheet:

It is used for data collection. A frequency of factorized data is collected in kiểm tra sheet.

6. Scatter Plot:

Scatter plot represents the relationship between two variables. It shows, how one variable changes with respect khổng lồ any change in another variable. Scatter plot can depict following relationships:

Svào positive

Svào negative

Weak Positive

Weak Negative

Any trend (Parabolic)

No relation

7. Control Chart:

These charts are used khổng lồ kiểm tra, whether process data remains under control for the shorter time span. They involve sầu process control limits & sometimes customer specification limits as operational ranges or bands. Process data is analyzed to lớn remain within process control limits. Whenever data goes out of control limits, it certainly has some special causes – to be investigated & removed immediately. The ayên ổn of these charts is lớn ensure process data doesn’t go beyond control limits. However, some exception rules are also there to lớn ascertain the condition of a process going out of control, while well within control limits.

Describing DMAIC - each phase one by one:

Image Source: http://www.free-management-ebooks.com/news/six-sigma-dmaic/Figure 3: DMAIC as a continuous improvement cycle

The process and tools associated with each phase are explained in following sections -


The main objective sầu of this phase is lớn summarize the project plan. This phase focuses on clearly specifying the problems; the goals of the process improvement project what is the scope of the project & identifying the customers (internal và external) along with their requirements. An input đầu vào to this phase comes from the voice of customer (VOC), the voice of business (VOB) and/ or the voice of process (VOP). In addition, sometimes the voice of employees (VOE) is also effective to lớn lead some six sigma improvement projects. With the help of these inputs, six sigma projects are identified. In this phase, we identify opportunity for six sigma projects. We develop a project plan and high-màn chơi process maps. The main component of this phase is preparing Project Charter. Charter is a document, which is an initial blueprint for any six sigma project. It outlines following essential elements:

Business Case: It helps khổng lồ underst& how the project is linked to lớn the overall business objectives.

Problem Statement: describes the problem or issue, this project is intended for.

Goal Statement: defines the project goal by considering all elements of SMART. The acronym stands for Specific, Measurable, Attainable, Relevant & Time-bound.

Project Scope:This considers in và out for this project. It defines the project boundary.

Team & their broad responsibilities: Project team mô tả tìm kiếm along with their responsibilities và roles during the project.

Time plan: Also, known as milestones. It ensures to keep a traông chồng on project progress as scheduled.

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Estimated project benefits: Project benefits need to lớn be estimated as a deliverable. Cost-benefit analysis is conducted & benefits, both tangible và intangible are speculated. This gives a direction to lớn top management, whether lớn approve the project.

Charter is duly signed và approved by top management. Thus, gives a signal lớn go ahead for outlines project from Top executive sầu. Tools in Define phase are required khổng lồ measure CTQ (Critical to lớn Quality) characteristics. The Parekhổng lồ Chart và SIPOC (Suppliers, Inputs, Process, Outputs, Customers) are the valuable tools of this phase.


The main objective sầu of this phase is lớn collect the data that is relevant to lớn the scope of the project. This phase focuses on identifying the parameters that need khổng lồ be quantified, ways lớn measure them, collect necessary data và carry out measurement by different techniques.

The operational definition of metric is devised. It gives comtháng language và understanding of data being collected. Data Collection plan outlines what data khổng lồ be collected? When khổng lồ be collected? Who will collect? Hence, sets overall direction for data collection.

After data collection, data is analyzed to ascertain its nature through frequency distributions. The histogram can be used to lớn underst& the distribution of data. Depending upon data nature – Normal or Non – Normal, data - analysis tools are decided. Current Process capability is also an important aspect to lớn be understood in this phase.

In Measure phase, different tools can be used lượt thích Process flowcharts, Benchmarking, Run charts, Gage R và R and Process capability.

Two commonly used measurement techniques are – Defects Per Million Opportunities (DPMO) and Process Sigma.


The main objective of this phase is lớn find the root cause of business inefficiency. It identifies the gaps between actual và goal performance, determine its causes & opportunities for its improvement.

Analyze phase follows a drill down approach khổng lồ reach exact root causes from various potential causes identified initially.

This phase starts with exploring all possible causes khổng lồ the main problem. Then, these causes are verified và validated though hypothesis & statistical tools. The outcome of this phase is verified root causes – which need lớn be acted upon to lớn improve the process. Analyze phase requires due care lớn identify & verify root causes. Because the effectiveness of process improvement through six sigma project lies on the correct identification of root causes.

Commonly used tools in Analyze phase are Fishbone Diagram, Brainstorming, Histogram, 5 Whys, Hypothesis testing, Time series plots và Scatterplot.


This phase improves the process by determining potential solutions, ways to implement them, demo & implement them for improvement. In this phase, process owners are consulted and improvements are suggested. Action plan for the improvement is circulated to relevant stakeholders. This action plan specifies – kích hoạt lớn be taken; By when By whom etc. The improvement plan is designed khổng lồ mitigate the risk & include customer feedbachồng & satisfaction. With the formation of improvement action plan, implementation phase starts simultaneously. During implementation, actions are carried out, tested for effectiveness & implemented finally.

Tools used to eliminate the defects are Brainstorming, Mistake-proofing (Poka Yoke), Simulation software, Prototyping, Piloting và Pugh Matrix.


The main objective sầu of this phase is to lớn generate a detailed solution monitoring plan. This plan ensures that the required performance is maintained. It defines và validates the monitoring system, develops standards và procedures, verifies benefits & profit growths, and communicates to business. Hence, the main purpose of Control phase is to ensure – Holding the gains.

During this phase, post-implementation results are evaluated. Progress is ascertained. And Changes are incorporated - if any, correction or modification is required. Control phase in most of the cases is a transition phase. Transition happens from current practices và systems into new practices.

The most important part of this phase is to lớn provide training on new changes khổng lồ all relevant stakeholders.

Important tools used in control phase are Process sigma calculation, Control charts, Cost saving calculations & Control plan.

Six Sigma – A top-down approach:

Six Sigma needs a drive sầu & support from top management to lớn realize its full potential. Hence, it’s a top-down approach. Top management commitment is a key khổng lồ success of Six Sigma projects. Six Sigma Master Blaông chồng belts or Blaông xã belts should seek for the best possible management support to lớn bring successful six sigma improvements. Apart from top management, commitment from all stakeholders và employees lead to exceptional outcomes. In the organizations, where six sigma is a part of organizational culture, excellence is pursued in each work area. Six Sigma approach is highly driven by the culture & values of the organization. The pursuit of continuous improvement & being excellent is an obvious buy- inkhổng lồ six sigma applications.

Final Takeaway:

Six Sigma DMAIC methodology has been internationally accepted & can be implemented in small-form size to lớn high-profile firms. Six Sigma is highly structured & logical methodology. The structure followed passes through five sầu important phases – DMAIC. The output from one phase is treated as input to lớn next phase. And in the kết thúc, results are obtained as per expectations. All these five sầu phases- define, measure, analyze, improve sầu và control – size a circular chain of continuous improvement. Six Sigma is a quest – a journey for improvement doesn’t over by reaching one milestone. This process improvement tool can be used incessantly khổng lồ realize continuous improvement. Hence, leading lớn excellence.

Be a part of excellence team by applying six sigma process improvement methodology in your organization. And improve sầu bottom line profits & customer loyalty. Six Sigma will be rewarding to lớn you và your organization.