A Guide to Root Cause Analysis
All manufacturers must have processes in place to control any product that does not conform to the specified requirements put in place by the regulatory body. When problems occur, it’s often root cause analysis that helps find a solution. Root cause analysis is the act of identifying the root cause of a problem, as opposed to simply treating the symptoms.
Firstly, let’s define ‘problem’. A problem is when something happens that is not supposed to happen or is different to what should have happened. The root cause is the core issue that sets in motion a cause-and-effect reaction, eventually leading to the identified problem occurring.
This step-by-step guide to root cause analysis takes you through the process, from identifying the problem right through to implementing an effective solution.
Problem occurrence
The first step in root cause analysis is to gather data on the problem you have identified. This data should give an indication of how widespread the problem is – how often it occurs, how long it’s been occurring, and what impact it’s having. Your data should be measurable and objective.
Problem statements
Next, you should write a problem statement. A problem statement is a concise definition of the problem that has occurred. The aim of a problem statement is to clearly identify and describe the problem that needs to be solved. It’s necessary for the investigation because it avoids any guesswork and ensures that everyone involved in the root cause analysis process is on the same page.
The problem statement should answer the following questions:
What product or process is involved?
How was the issue discovered?
Where was the issue discovered?
When was the issue discovered?
Who discovered the issue?
Why is it a problem?
Remember to focus on the actual thing that happened versus what was expected to happen. It is useful to include measurable and objective evidence that supports your interpretation of the problem, too.
Containment
Once the problem has been clearly identified, the next step is to complete a risk assessment to determine the likelihood of the problem causing injury, and the likely severity of any injury. If the problem involves a medical device, a medical practitioner should be consulted as part of this process.
Once the level of risk has been identified, you can decide on suitable product containment action. Containment action is the immediate steps that must be taken in order to limit the potential impact of the identified problem. These steps are temporary and are usually put in place only until a long-term solution is found.
Containment action may include carrying out additional inspections on products already in use, removing a suspect part or piece of equipment from existing products, or as a last resort, withdrawing products from use. Whatever course of action you choose should be consistent with the identified level of risk.
Corrective action
Corrective action is the steps that must be taken in order to resolve the problem and resume normal activity. Corrective actions may also include preventative actions – steps taken in order to prevent the problem from happening again in the future.
While it can be tempting to jump into a quick solution, proper corrective action gets to the heart of the problem and ensures it doesn’t reoccur. This includes addressing any contributing factors that come with the root cause of the problem, to prevent them from becoming root causes in the future. So, deciding on a course of corrective action is often the most time-consuming part of root cause analysis.
Before choosing a course of corrective action, you should:
Ensure the solution is viable in respect of the timeframe and resources available
Consider the expected effectiveness of the solution
Compare the chosen solution to alternative solutions using measurable, objective data
Derive a backup plan to have in place in the event that the agreed solution doesn’t have the expected outcome
Remember that in most cases, there will be no absolute correct solution. So, you may have to consider whether your chosen course of action will lower the risk of the problem reoccurring to an acceptable level, rather than eliminating it altogether.
Effectiveness checks
Once corrective action has been taken, the next step is to make sure it has been effective in solving the problem and preventing it from recurring. Until this step is complete, you cannot officially consider the problem corrected.
Effectiveness checks may include one or more of the following:
Trend analysis of data over time, to check whether the corrective action has remedied the issue
Periodic checks
Surprise audits
Sampling
Checks should be implemented within an agreed timeframe. The timeframe should allow enough time for the corrective actions to take effect, while at the same time taking into consideration the impact that any delay could have.
Once you are satisfied that the corrective action taken has remedied the problem and that it is not expected to happen again, you can consider the root cause analysis to be complete.
To sum up
Root cause analysis is recommended as a means of identifying underlying problems with products and coming up with effective solutions. Only when you address the root cause of a problem can you be confident that it won’t happen again. By following the steps outlined above, you should be well-equipped to deal with any problems that arise, ensuring that any resulting impact is contained and that the problems don’t reoccur in the future.