ROOT CAUSE ANALYSIS – Digging deeper than symptom:
A systematic approach to get the true root cause of the problem.
The purpose of the root cause analysis is to improve the product or processes by getting the bottom of the problem or unexpected event by
Identify the factor that produced the problem
Determine what behaviors, actions & conditions need to be changed; to prevent re occurrence.
CAUSE:
A set of conditions or circumstances that
Allows a condition to exit or event to happen, or
Makes a condition exist or event happen
ROOT CAUSE:
The fundamental reason for an event which if corrected, would prevent re occurrence.
A factor that caused the non-conformance. When we fix it, the problem goes away and does not come back.
We must be ever vigilant of the difference between problem symptoms and problem root causes. Examining the analogy of a weed in your lawn is helpful in seeing the difference. The weed is the symptom; it is what you see above the surface. Cutting the weed, even at ground level is rarely helpful because the root of the weed is still alive and will regrow the weed which you will see at a later date. By not digging the root of the weed out of the ground is analogous to not “getting to root cause”.
ROOT CAUSE ANALYSIS – Philosophy & Approach:
Each problem is an opportunity because it can tell a story why and how it occurred.
True problem must be understood before action taken. Root case analysis is a collective term that describes a wide range of approaches, tools and techniques used to uncover the cause of problems.
Root cause analysis Approaches: But not limited to
1. Four step method (PDCA & Form, Norm, Storm, Perform)
2. Five Step method (DMAIC)
3. Six step method
4. Eight step method (8D Method)
5. Nine Step : Boeing
6. Toyota A3
7. Kepner Tregoe method
Root cause analysis Tools: But not limited to
1. Genchi & Genbutsu (Go & See)
2. Brain storming
3. Fish bone analysis / 6M Method / Ishikawa diagram / Cause & effect diagram
4. Why-Why analysis
5. Pareto Charts
6. Run Charts
7. Control Charts
8. Flow charts
9. Histogram
10. Scatter diagrams
11. Affinity diagrams
12. Tree Diagram
