Is–Is Not Analysis

Introduction: Is–Is Not Analysis

Is–Is Not Analysis is a structured problem-solving tool used to clearly define problems by distinguishing between what is happening and what is not. It eliminates ambiguity and narrows the scope of investigation, making it especially effective in quality improvement and root cause analysis.

Background

Developed within quality management and Lean Six Sigma practices, the method provides a systematic framework to clarify problems before attempting solutions. By contrasting “is” with “is not,” it reduces guesswork and ensures that teams base their analysis on facts rather than assumptions.

Key Elements/Features

• Objective: Define the problem with precision, ensuring all stakeholders share the same understanding.
• Guiding Questions:
  • Who is involved?
  • What exactly is happening?
  • When does it occur?
  • Where does it occur?
  • Why is it significant?
  • How often does it happen and how severe is the impact?
• Categorisation: Answers are divided into two columns: “Is” (confirmed facts) and “Is Not” (excluded conditions).
• Analysis: Differences between the two lists help highlight patterns and narrow down possible root causes.

Applications/Examples

• Manufacturing: Determining whether a defect occurs only in a specific machine, shift, or material batch.
• Healthcare: Clarifying whether delays happen only in certain departments or during specific times.
• Service Industry: Identifying if customer complaints apply to all services or only particular ones.

Relevance/Impact

Is–Is Not Analysis is highly valuable because it reduces noise and confusion in problem-solving. It ensures alignment among team members, directs attention to relevant variables, and speeds up the identification of root causes. By improving clarity, it supports data-driven decision-making and more effective corrective actions.

See also

• Root Cause Analysis (RCA)
• Five Whys
• Pareto Analysis
• Failure Mode and Effects Analysis (FMEA)