What Is Six Sigma?
Generally, Six Sigma is a problem-solving methodology that helps enhance business and organizational operations. It can also be defined in a number of other ways:
- A quality level of 3.4 defects per million opportunities
- A rate of improvement of 70 percent or better
- A data-driven, problem-solving methodology of Define-Measure-Analyze-Improve-Control
- An initiative taken on by organizations to create bottom-line breakthrough change
Six Sigma Principles
Six Sigma is based on a handful of basic principles, and these principles create the entire Six Sigma arrangement. Here are Six Sigma’s fundamental principles:
- Y = f(X) + å: All outcomes and results (the Y) are determined by inputs (the Xs) with some degree of uncertainty (å).
- To change or improve results (the Y), you have to focus on the inputs (the Xs), modify them, and control them.
- Variation is everywhere, and it degrades consistent, good performance. Your job is to find it and minimize it!
- Valid measurements and data are required foundations for consistent, breakthrough improvement.
- Only a critical few inputs have significant effect on the output. Concentrate on the critical few.
The Six Sigma Scale
The Six Sigma scale shows how well a vital feature performs compared to its requirements. The higher the sigma score, the more efficient the feature is. This table shows the universal Six Sigma scale:
|Sigma Level (Z)||Defects per Million Opportunities (DPMO)||Percent Defects (%)||Percent Success (Yield %)||Capability (CP)|
The DMAIC Method of Six Sigma
The DMAIC (Define-Measure-Analyze-Improve-Control) project method is a formalized problem-solving process of Six Sigma. It’s made-up of five steps to apply to any procedure of a business to improve effectiveness.
- Define: Set the context and objectives for your improvement project.
- Measure: Determine the baseline performance and capability of the process or system you’re improving.
- Analyze: Use data and tools to understand the cause-and-effect relationships in your process or system.
- Improve: Develop the modifications that lead to a validated improvement in your process or system.
- Control: Establish plans and procedures to ensure that your improvements are sustained.
The Tools-Methods Landscape of Six Sigma
Having the right tools and knowing how to apply them to your Six Sigma projects will help you produce accurate, acceptable, and reusable outcomes.