Have you ever found yourself needing to resolve a quality problem only to be at loss in identifying whether the actions to be taken fall under correction, corrective action, or preventive action? The key to tackling this dilemma is to understand the distinction between the three types of actions and each should be applied.
To start, let’s understand what it is we want to act upon. A quality problem is typically known as a nonconformity or nonconformance. The Quality System Regulation and ISO 9001 both define nonconformity as the nonfulfillment of a specified requirement. These regulations require the identification, documentation, evaluation, segregation, and disposition of nonconforming product, in addition to a determination of the need for an investigation, among other things. For the nonconformities that are investigated, there is a determination of root cause(s) that requires action be taken to eliminate or reduce their effect.
The first type of action, correction, is a change that makes something right, true, accurate, etc. or the act of making something (such as an error or a bad condition) accurate or better. The regulated industry defines correction as action taken to eliminate a detected nonconformity. Corrections are typically one-time fixes, sometimes known as remedial actions, and are typically aimed at addressing the symptoms rather than causes of a quality problem, much like first aid. These actions do nothing to address root causes or prevent reoccurrence of the quality problem. A few examples of common corrections include rework, reprocess, regrade, scrap, return-to-vendor, and use-as-is.
A corrective action, on the other hand, is action taken to eliminate the causes of a detected nonconformity or quality problem. This action is intended to eliminate the recurrence of a quality problem that has occurred. A preventive action is action taken to eliminate the cause(s) of a potential nonconformity or potential quality problem. This action is intended to prevent the occurrence of a quality problem that has not yet occurred but has the potential to occur.
This may all sound confusing, as it was for me when I started working in the regulated industry 20 years ago. Let me share my Aha-moment, which was triggered by an analogy made by a co-worker running our CAPA program at the time.
Let’s say a person has a headache (symptom of a quality problem), decides not to visit a doctor (investigator), and simply takes some medication to make the pain go away (correction). This action did not require an understanding of what was triggering the headache (root cause) and therefore does nothing to prevent the recurrence of the headache. This person has treated a symptom by taking a correction action, which is a one-time fix for this particular headache. This action requires no confirmation of effectiveness that ensures the headache or whatever is causing it is gone for good.
Now, let’s say the person continues to suffer from headaches (recurrence of the problem) and decides to visit a doctor (investigator) to understand what is causing the headaches. Since there are many potential causes for severe headaches, the doctor may require blood work, pressure tests, a brain scan or a stress test to diagnose the patient (root cause analysis). Once all the tests come in, the doctor will evaluate potential causes based on the objective evidence provided by the test results. Some potential causes may get ruled out based on evidence while others may lead to further analysis until a diagnosis is made (root cause(s) is identified and confirmed).
For the sake of this example, let’s say the patient was found to have high blood pressure (another symptom). Would treating the patient with medication to lower blood pressure be a good corrective action? I might have said yes early in my career, but understanding that this is just another symptom, I’d now say no. A good doctor (investigator) would want to understand why the patient has high blood pressure. Additional tests are ordered to validate the most probable root cause, and the doctor concludes that high sodium levels are causing blood pressure to rise, which triggers the patient’s headaches. An analysis of the patient’s habits and lifestyle lead to the discovery that a high salt, saturated fat and cholesterol intake and lack of exercise are causing the problem. The doctor can now prescribe corrective action, for example, a specific balanced diet and 30-minute daily physical routines combined with yoga to de-stress. One type of preventive action would be applying these dietary and exercise recommendations to the rest of the family members to prevent them from ever having high blood pressure due to these causes. An even better application of preventive action is making additional healthy lifestyle changes to prevent potential health issues from ever occurring.
The doctor will require follow up tests sometime after applying corrective actions to confirm that sodium levels are low, blood pressure is under control, and the patient no longer suffers from headaches. This is called verification of effectiveness, which demonstrates that actions have addressed the root causes of the problem to reduce or eliminate their effect, depending on the goal of the CAPA.
Various challenges that quality folks experience in this area are:
- Mistaking correction as a means for “little” corrective actions; since corrections do not require verification of effectiveness, you may run into quality issues
- Stopping the root cause investigation too early; folks end up addressing symptoms rather than causes and see the problem recur over time
- Stopping investigation once a root cause is identified; many times, problems have multiple factors and if not addressed, the problem will recur
- Failing to apply actions where the problem has the potential to occur; many CAPAs lack the preventive aspect and you will eventually see problems recur in different areas
- Failing to invest adequate resources in corrective and preventive actions; solutions are not robust and fail effectiveness check by not meeting the established goal
The distinction between the three concepts can be summarized as:
- Correction: Remediation of an identified quality problem (first-aid to address symptoms)
- Corrective action: Actions to address identified root causes of the quality problem to prevent its recurrence (diagnosis and prescribed treatment)
- Preventive action: Actions taken to avoid occurrence of a potential quality problem (proactive healthy lifestyle in anticipation of potential issues)
Understanding the types of actions required at different stages of the CAPA process is key to the success of the overall quality program in ensuring safe and effective products.