Six Sigma 101: Two

Process Improvement and Six sigma

Six Sigma Improvement Models: Two Paths to Success
by Diane Ritter and Michael Brassard

At its simplest, Six sigma can be described as:

"a program to accelerate profits and customer satisfaction by systematically eliminating the root cause of critical defects or errors in all processes, or by creating new, more effective processes."

This definition, then, suggests two paths a team would take depending on the situation.

Defining DMAIC vs DFSS/DMADV
Dr. Deming reintroduced the world in 1950 to the scientific method known as the Plan-Do-Check-Act (PDCA) Cycle for continuous improvement. However, it is the "CAPDo" cycle that is the heart of Process Management. It simply means that daily improvement starts with a "check" on performance, which uncovers "gaps" that need to be filled. "PDCA" is used when a new product, process, or service is first developed; eventually becomes part of an ongoing Process Management and CAPDo cycle.

The PDCA/CAPDo cycle was translated into two practical 6-step approaches for teams to use during their problem solving/process improvement and new product design efforts.

If the team effort is to...	the Cycle...	Translates to this model...
Improve the current process	CAPDo	DMAIC
Create a new, well-designed process	PDCA	DFSS/DMADV

DMAIC
DMAIC, pronounced de-MAY-ic, represents the 6-step approach for teams to use during their problem solving/process improvement efforts:

Define, Measure, Analyze, Improve, Control

DMAIC is used when there is a significant performance gap in a process that's critical for both the financial health of the company and the satisfaction/loyalty of customers. It, along with the DFSS (Design for Six Sigma) process, is the engine behind any Six Sigma implementation. In order for Six Sigma to become a way of life, the DMAIC process must be taught rigorously to all Black Belts and Green Belts. These "improvement experts" then train the rest of the organization by using the DMAIC process as they lead Six Sigma projects.

Who uses DMAIC?
Every Six Sigma project team that's working to improve an existing process that's failing to satisfy the needs of the customer and/or the performance of a competitor.

How is DMAIC done?

DEFINE: Select an appropriate project and define the problem, especially in terms of customer-critical demands - the "Performance Gap." This is the step in which the size of the improvement opportunity is determined, targets are set, the team is formed and the project is developed.
MEASURE: Gain information about process performance and develop a problem statement. During this step the team is examining the way work is currently done and measuring the results against what's required by the customer. The team uses data-analysis tools to break down the problem until the "vital few" become apparent. This produces the problem statement that's the focus for the rest of the project.
ANALYZE: Analyze the causes of the problem and verify suspected root cause(s). The team systematically (and repeatedly) asks why the problem is occuring and uses data to confirm their conclusions. It combines the incessant curiosity of a two-year-old with the data-driven discipline of a scientist.
IMPROVE: Identify actions to reduce defects and variation caused by root cause(s) and plan the implementation of selected actions. This is the solution phase in which the process is adapted to hit Six Sigma-level targets. In fact, in some cases the team may decide that the current process must be scrapped/re-engineered if there are any hopes of achieving Six Sigma performance. This can even lead to the use of the DFSS (Design For Six Sigma) model for the creation of fundamentally new processes. In most cases, the team continues the DMAIC process by creating the final implementation plan.
IMPLEMENT: Evaluate the measureable improvement (if not evident, return to step one). The team must now sell the solution, which MUST include the needed training and monitoring of both the plan and its results. It's critical that the team knows whether the plan was implemented as designed and whether the plan achieved its targets. Seek to understand both the what AND the how of the results of the project.
CONTROL: Control the process to ensure continued, improved performance; determine if improvements can be transferred elsewhere; identify lessons learned and next steps.

DFSS/DMADV
Design For Six Sigma is a process that focuses on designing a new product or service that is capable of delivering Six Sigma level quality. It uses the DMADVI model:

Define, Measure, Analyze, Design, Validate

DMAIC, with its cost-savings impact, is the primary focus for the early stages of Six Sigma implementation. It can be (and is) used to generate new revenue, but his outcome is the real strength of the DFSS process. It's critical to stress this "growing-the-business" dimension of Six Sigma since revenue growth is at the heart of every business model. If Six Sigma is seen as an ongoing growth "engine," managers at all levels will view it as part of the permanent management system, not as an initiative that can be ignored.

The Basics of DFSS
At its absolute simplest DFSS focuses on:

Systematically understanding and converting customer needs into Critical-To-Qualities (CTQ's).
Designing production/delivery processes from the ground-up with statistically determined Six Sigma capability.
Piloting and confirming the capability of the new production/delivery process.
Building full-scale processes with built-in control and improvement mechanisms.

Rather than using the DMAIC improvement model, DFSS is based on the DMADV model.

Who Participates in a DFSS/DMADV Project?
Just as in a DMAIC project, a DMADV team can vary from a group of single-p;specialty scientists (a team of first-rate metallurgists) to a completely cross-functional composition. It's entirely dependent on the nature of the process or system that's being tackled. It's particularly critical to maintain the smallest possible core team that can be supplemented by ad hoc members as the project requires. Since a DFSS effort is building a product or process from the ground up, the core team generally needs to have members with intimate knowledge of the underlying principles and requirements of the new product or process. In other words, DFSS efforts often require process or product "experts" to form the nucleus of the team with other "generalists" brought into the process as needed.

How is DMADV done?

DEFINE: This step is virtually identical to the DMAIC process. It focuses on identifying the size and scope of the opportunity, while making sure that DMADV is the best fit for the situation. It's also about building the most effective, efficient team with clearly defined goals supported with a well-thought out project plan.
MEASURE: While this step in the DMAIC process measures the performance of the current process, DMADV focuses on measuring (and quantifying) the expectations and requirements of customers. The team is building a a product/service profile against which design alternatives will be compared. The Six Sigma targets set in this step will define the success or failure of the DFSS project.
ANALYZE: This step combines the practicality of turning customer requirements into product/service functions with the creativity of generating and testing new concepts to fulfill those functions. The team must also create a design of a new production process along with its capabilities. A number of iterations are usually needed to get these process concepts up to Six Sigma level performance, even on paper. This is the step of small-scale experiments with very rapid PDCA cycles.
DESIGN: The team (torture tests) the most promising product/service design(s) by developing detailed production plans and their likely failure modes. Based on more realistic picture of process capability, the team must make tradeoffs between product/service features and functions and the level of reliability that production processes can consistently deliver. This is also where process control plans are designed and built right into the proposed production process.
VALIDATE: Since DMADVI is a (from-the-ground-up) process, small-scale experiments make the most sense for two reasons: First, pilot implementations minimize both the cost and the risk of trying something entirely new. Secondly, the PDCA cycle can be turned very quickly, making it possible to dramatically accelerate the team's learning curve. Once performance gaps have been uncovered and root causes eliminated, the team must design the quality management and production control systems needed to move to full-scale implementatioin. Finally, the team must create a transition schedule to the full-product production/service delivery.

There is an implicit last step to EVERY Six Sigma project team: Celebrating and recognizing the hard work of the team, while documenting the lessons which were learned about the DMADV process itself. Without these shared learnings, the (process capability) of the Six Sigma implementation process itself will never begin to approach Six Sgima quality.

Excerpted from Sailing Through Six Sigma