What is Six Sigma?

Six Sigma is one example of a quality methodology that assists with process improvement initiatives. From a statistical perspective, Six Sigma is a measure of variation. A process is said to be “Six Sigma” when it yields no more than 3.4 defects per million opportunities. To put that in perspective, suppose there is an invoice entry process whereby a manual entry is required. That would mean only 3.4 manual entry errors per million manual entries!

Six Sigma as a quality improvement methodology focuses on reducing process variation and eliminating waste and defects. Statistics are heavily used during Six Sigma projects. Decisions are made based on data rather than on “gut feel.”

Six Sigma got its start in 1986 when Motorola designed the methodology for its manufacturing processes. Based on the company’s success with the program, Motorola expanded its use to all business functions within the entire organization. Six Sigma projects yield Return on Investment between 10:1 and 50:1, and Motorola savings of over $20 billion can be attributed to Six Sigma. Motorola also won the Malcolm Baldridge National Quality Award in 1988 and 2002 – a testament to Six Sigma! (Source: www.motorola.com)

The Six Sigma methodology for process improvement follows the DMAIC process – Define, Measure, Analyze, Improve, and Control. During the Define phase, the problem statement is developed, the customers critical to quality requirements are identified, and the project scope and objectives are defined. During the Measure phase, the as-is process is mapped, process performance is baselined, and improvement goals are established. During the Analyze phase, the process is analyzed and the critical drivers that affect performance are identified. The causes of process variation and defects are identified and validated. During the Improve phase, the improvement solution choices are created, evaluated, selected, and implemented. During the Control phase, the improvement goals are verified and controls are put in place to ensure that the improvements are sustained over time.

Formal Six Sigma projects are fairly rigorous and require sponsor support in order to be successful. One pitfall that is often experienced by improvement project teams is that they jump to solutions early and do not allow the methodology to lead them. Many process improvement projects may not warrant the rigor of the DMAIC process as it is formally prescribed, but the general steps and tools can be used to fast-track process improvement initiatives to deliver measurable results.

Six Sigma is not a fad – the application of Six Sigma has spread to various industries over the years, including: education; manufacturing; service; government; information technology; financial/banking; marketing; software development; healthcare…the list goes on and on. Regardless of the industry that you are in, Six Sigma can be used to deliver results.

By Jeanne Mavis, Manager, Quality Assurance;
Six Sigma Green Belt Certified; Six Sigma Black Belt Candidate