Six Sigma DMAIC Process - Control Phase - Review and Sign-off

The project closes when defect reduction has been demonstrated over an agreed verification period. The Black Belt and Master Black Belt agree on the time needed to collect and analyze the data. If the improvement is not confirmed, reopen the project. Confirmation runs check whether the improved process delivers the expected result. Where a planned on/off comparison is feasible and appropriate, comparing the old and improved conditions can help determine whether the problem returns under the old conditions; this is not a requirement to reintroduce defects into normal production.

The purpose of the comparison is to distinguish the improvement’s effect from shifts, drift or changes in other variables. Plan the comparison and account for those factors so they do not lead to the wrong conclusion. The Six Sigma Champion, Black Belt, deployment leader, finance manager, process manager and functional head sign the project’s financial scorecard. The leadership team agrees with the stated benefits.