Common Cause Variation vs. Special Cause Variation: Key Differences

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Common Cause Variation vs. Special Cause
Variation Key Differences
It is quite essential to understand variation
pertaining to process involvement and quality
management, for achieving organizational success.
Variations are of two types Common Cause
variation and Special Cause Variation. Both types
play a significant role that helps determine the
stability and performance of processes.
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We will explain the key differences between the
two types of variation with the help of
real-world examples for a better understanding.

1. Common Cause Variation
2. Special Cause Variation

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Common Cause Variation

• Common cause variation is innate and a natural
  part of any process and its operation. It depicts
  normal fluctuations that occur over time due to
  factors innate in the process itself. The process
  operates within certain statistical limits under
  normal conditions. Hence, it is stable and
  predictable.
• Examples
• Daily fluctuations in call volumes at a customer
  service center.
• Minor variations in product dimensions during
  manufacturing.
• Variability in delivery times for routine
  shipmentsx

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Special Cause Variation

• Special cause variation is caused by an external
  factor. It is not innate in the process and leads
  to outcomes that are unpredictable and uncommon.
  Special cause variation can lead to striking
  deviations as opposed to expected and stable
  outcomes.
• Examples
• Machine breakdowns leading to production delays.
• Employee errors resulting in quality defects.
• Supplier issues causing disruptions in the supply
  chainx

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Key Differences

1. Nature
2. Predictability
3. Management Approach

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Nature

• It is innate and a natural part of any process
  and its operation with natural fluctuations
• Special cause variation is caused by an external
  factor. It is not innate in the process.

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Predictability

• Common cause variation is predictable and stable,
  operating within certain statistical limits.
• Special cause variation is unpredictable and can
  result in significant deviations from the
  expected performance of the process..

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Management Approach

• Common cause variation requires process
  improvements and adjustments to reduce
  variability and enhance stability over time.
• Special cause variation requires immediate
  investigation and corrective action to address
  the root cause and prevent recurrence.

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Conclusion
Two types of variation impact process stability
special cause (external factors with unexpected
effects) and inherent (natural oscillations).
Effective management practices and understanding
these variations can optimize performance and
drive continuous improvement in
organizations.Are you looking for an
opportunity to learn more about quality
management? MindCypress offers Lean Six Sigma
Green Belt certification training and Lean Six
Sigma Black Belt certification through live
online training. The online training equips
learners with the necessary knowledge and skills
to start their careers in their desired fields.
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Closing Slide Resource
Resource https//www.mindcypress.com/blogs/qualit
y-management/common-cause-variation-vs-special-cau
se-variation-key-differences