Basic Tools: Effective Six Sigma via Statistical Thinking – Taken from Spring 2003 Newsletter

Abstract: Six Sigma has proved to be an outstanding approach for improving processes and its applications are expanding from manufacturing to other areas such as health care, finance, services, etc. The article states that unleashing the full potential of Six Sigma requires the use of statistical thinking. The article presents definitions and important features of statistical thinking and Six Sigma. Six Sigma and statistical thinking should be intrinsically embedded. The article warns that measuring Six Sigma project benefits solely on monetary figures (costs) will not produce long term results. Statistical Thinking is a process-oriented approach to reducing variability. Six Sigma projects should seek a full understanding of the system, use statistical thinking to reach more robust solutions and reduce variability by tackling key inputs. Several examples illustrate the technical failures resulting from inadequately applying statistical thinking on Six Sigma projects. Finally, the article presents four principles for improving Six Sigma projects.

Keywords: DMAIC (Define - Measure - Analyze - Improve - Control - Statistical thinking - Control charts