Authors: Syed Shahabuddin
Addresses: Smith 203C, Central Michigan University, Mount Pleasant, Michigan 48858, USA
Abstract: Companies are concerned about quality control. There are many methods of controlling quality, such as control charts, Total Quality Management (TQM), Six Sigma and others. However, the current emphasise on Six Sigma suggests that organisations should achieve 3.4 defects per million. Even though it is a target, it is neither practical nor statistically-based on quality control charts. Moreover, the current literature discusses the benefits of Six Sigma without providing solid economic and/or statistical proof that it works. This paper discusses the problems with Six Sigma and shows how it is impractical and statistically unsound. It also suggests that other tried and true quality control methods which have worked and are statistically sound.
Keywords: quality control charts; six sigma; total quality management; TQM; normal distribution; capability index.
International Journal of Productivity and Quality Management, 2008 Vol.3 No.2, pp.145 - 160
Published online: 11 Jan 2008 *Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article