What is Root Cause Analysis (RCA)?
Root Cause Definition
Root Cause Analysis (RCA) is a set of analyzing and problem-solving techniques with the goal of identifying the true root cause or the reason for the nonconformity. RCA is imperative to organizations because it does not just eliminate symptoms of the problem, but rather, it finds the actual problem and addresses the problem from the source. If you are able to identify the source of a problem and fix that, the chances of the problem occurring again are low.
A root cause is just what it sounds like: the “root” of the problem.
Here is an example:
A tennis court looks sloppy because weeds are growing in the cracks.
- Cutting the weeds only eliminates the symptom as it may grow back.
- Killing/removing the root will eliminate the problem.
If there is more than one root cause discovered after analysis, all the causes have to be addressed for corrective actions to be successful. A root cause analysis is considered successful when the problem does not recur.
Oftentimes, organizations rush to solve problems and take immediate actions. These actions almost always will address the symptoms, but rarely do they actually find the source of the issue. Although your organization may find immediate relief, this is not a sustainable approach as the actual problem was not fixed. Ideally, your organization should spend time troubleshooting to understand where the issue is arising from and correct the source of the problem or the “root cause”. Various methods can be used to determine the true root cause, such as 5 whys or cause and effect diagrams.
Steps in Root Cause Analysis
- Identify the problem/non-conformance clearly.
- Once a candidate for RCA (or the problem or the non-conformance) has been identified, gather sufficient information about it.
- Ask What, How and When about the problem and document it.
Perform the Analysis
- Use any of the root cause analysis tools & techniques for performing the analysis.
- Use your logic and choose the best possible way to solve the problem in a simple, effective, and least expensive method. Take care to eliminate the non-probable causes.
Implement the Solution
- Recommend and implement the best solution.
- Also take care to see that these corrective actions do not induce any other related or unforeseen problems. Check that the problem does not recur.
- Use the data from the learning and analysis of the RCA and use it in the continuous improvement projects.
Can we really eliminate the Root Cause?
There may be times that you may be unable to remove the root cause completely, but the more you understand a problem the better the chances you have to prevent its recurrence or at the very least minimize the likelihood of recurrence.
Where is it useful?
RCA can be used in any field across any domain where the organization uses safety-based, production-based, process-based, failure-based, and software-based systems.
The most common tools and techniques used in RCA are:
- Fishbone (Ishikawa) diagram – used during brainstorming exercises when many possibilities of the resolution exist.
- Pareto chart – used to classify the problems based on the Pareto principle, which says 80% of the problems have 20% of the causes.
- Cause and Effects diagram – used to find the causes and effects of all possible causes of the problem.
- 5 Whys – used to determine the root cause by repeatedly asking “Why?”
Examples where RCA can be used or candidates for RCA:
- Resolution of customer complaints.
- Addressing non-conformances from an external or internal audit.
- Error/defects existing in a product.