What is Six Sigma?

Six Sigma is a performance improve-ment methodology that seeks to identify the key sources of variation in a process(critical factors) that cause defects to occur. By mapping processes, measuring their output, and analyzing its many input variables, Six Sigma determines how to optimize the output from a process by controlling the inputs. Six Sigma projects move through a disciplined framework (known as 'DMAIC')

Define the problem – in terms of performance, consequences and gaps from what is desired 

Measure the process – first to ensure the data is reliable, then to decide how well the process performs 

Analyze the variables – using statistical tests of significance, to find those variables that have the greatest impact on process yield

Improve the process – through small scale experiments and hypothesis tests to compare the impact, before and after

Control the process – to sustain gains and ensure process does not regress to previous levels