Previously I discussed three common cause strategies (links below) that help to expose all existing, underlying special causes of variation. They also provide necessary insight into how the current process came to be and allow construction of a baseline for assessing the effects of an intervention.

Common cause strategy No. 1: Exhaust in-house data in “Wasting Time With Vague Solutions, Part 2”
Common cause strategy No. 2: Study the current process in “Wasting Time With Vague Solutions, Part 3”
Common cause strategy No. 3: Process dissection in “Another Strategy for Determining Common Cause”

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