Sigma metrics

Abstract

The calculation of the Sigma metric is widely used to assess capability of assays and to use this as the basis for developing the Quality Control (QC) strategy varying the frequency of QC samples and the QC rules used. Assays with poor capability require more control with a higher frequency of QC samples and more sensitive QC rules. But more generally, Six Sigma is a management strategy that seeks to improve the quality of process outputs by identifying and removing the causes of defects (errors) and minimising variability in manufacturing and business processes.