Table of Contents
Root Cause Analysis
Root cause analysis is the identification of the root cause of a defect.
Basic root cause analysis can often be extremely illuminating if 50% of your software defects are directly attributable to poor requirements then you know you need to fix your requirements specification process. On the other hand if all you know is that your customer is unhappy with the quality of the product then you will have to do a lot of digging to uncover the answer.
Purpose of Root Cause Analysis
The objective of RCA is to identify “root cause(s)” so that these latent failures may eliminated or modified and future occurrences of similar problems or mishaps may be prevented.
Overview of Steps in Root Cause Analysis
Clearly define the undesired outcome.
- Gather data, including a list of all potential causes.
- Create an event and causal factor tree.
- Continue asking “why” to identify root causes.
- Check your logic and eliminate items that are not causes.
- Generate solutions that address both proximate causes and root causes.
Four Major Steps in Root Cause Analysis
The RCA is a four-step process involving the following:
- Data collection.
- Causal factor charting.
- Root cause identification.
- Recommendation generation and implementation.
Summary
To perform root cause analysis you need to be able capture the root cause of each defect. This is normally done by providing a field in the defect tracking system in which can be used to classify the cause of each defect.
Sub-classifications are also possible, depending on the level of detail you wish to go to. For example, what kind of requirement errors are occurring? Are requirements changing during development? Are they incomplete? Are they incorrect?Once you have this data you can quantify the proportion of defects attributable to each cause.
