When special cause variation is detected it is normally eliminated by increasing the number of standard deviations (Z value) used to calculate the control limits.

Question

Quizplus · Accepted Answer

Special cause variation cannot be eliminated by simply adjusting the control limits. Instead, the root cause of the variation must be identified and addressed in order to prevent it from occurring in the future. Adjusting the control limits may only mask the underlying problem and lead to false sense of security in the process.

When Special Cause Variation Is Detected It Is Normally Eliminated