How to search for root cause using Cause and Effect Chain Analysis?
Cause and Effect Chain is an excellent tool for root cause analysis. This tool will help you to understand the source of the problem and find a way to eliminate the problem. Using this tool you will find out a new brilliant idea that deserves a curiosity and following incarnation.
How it works
Cause and Effect Chain (CEC) analysis is based on a very simple idea – nothing happens without an origin, without an initiation, without driving, without reason. The purpose of the tool is to reveal a root cause of a problem, create new ideas and find the best solution to the problem.
CEC tool requires to create a logical chain answering the question “Why?” moving from “Target Problem” link by link down to a “Key Problem”. “Target Problem” – a problem under investigation. “Key Problem” – is a logical end of the chain.
As a result of the analysis, a chain chart should appear. The chain could be ramified depending on your analysis. A two-ramified chain is shown below as an example. Nevertheless, we all know that there is a very low probability for more than one reason caused at the same time the only effect. Do you believe that your car engine is not started due to no electricity and lack of gasoline simultaneously? We do not. Therefore, in the frame of root cause search, you would need to check each link of your chain and terminate irrelevant links. The only a single chain should remain for root cause analysis. A simple chain with no ramification is an important circumstance allowing to solve your problem successfully.
Step 1. Define and write your project title.
Step 2. Define and write the problem statement – formulate and describe the target problem.
Step 3. Write your target problem in the field “Target Problem”
Step 4. Think and answer the question “Why?”. Continue to answer the questions “Why?” creating your cause and effect chain until you get to the end, a dead end. A dead-end means there is nothing to do with this you cannot change it.
Step 5. Before you define the root cause let’s understand what root cause is? The traditional definition says:
A Root Cause is a fundamental reason for the occurrence of the problem – it might be good but not helpful. Typically, you can do nothing with a fundamental reason of an occurrence. There is a practical definition:
A root cause is a source of a defect such that if it is removed, the defect is decreased or removed. So the root cause is a reason that you have to choose to solve the problem.
Step 6. Think and write a possible solution for each cause that appeared in your Cause-Effect Cain;
Step 7. Rank the solutions and choose the most suitable for the realization.