Corrective vs preventive action
| Corrective action | Preventive action | |
|---|---|---|
| Trigger | A problem that has already happened, such as a deviation, non-conformance, complaint or audit finding | A potential problem identified through trends, risk assessment or near misses |
| Goal | Stop it recurring | Stop it occurring at all |
| Example | Fix the cause of a mislabelled batch | Apply the same label check to other lines before they fail |
Correction (fixing the immediate issue, such as reworking or quarantining product) is different again. It deals with the effect, not the cause.
The CAPA process
- Identify and record the problem with enough detail to investigate.
- Assess risk to decide priority and depth of investigation.
- Contain affected product, equipment or areas.
- Investigate the root cause using tools such as 5 whys or a fishbone diagram, verified with evidence.
- Plan actions that address the root cause, with owners and due dates.
- Implement the actions, including updates to procedures, training and standard work.
- Verify effectiveness using pre-agreed criteria before closing.
Verification of effectiveness
This is the step most often skipped. Confirming an action was completed is not the same as confirming it worked. Define success criteria when you plan the action, for example no recurrence across a set number of batches or a sustained shift in a key measure, then check against them after enough time has passed. If the problem returns, the CAPA reopens.
CAPA in regulated industries
In pharmaceutical, medical device and food manufacturing, CAPA is a core expectation of good manufacturing practice and quality system standards. Regulators and auditors look for documented investigations, rationale for actions, and evidence that effectiveness was checked. The same discipline works well in any operation that wants problems to stay fixed.
Common mistakes
- Defaulting to "retrain the operator" as the action.
- Closing CAPAs on completion date rather than proven effectiveness.
- Letting CAPAs age with no visible owner or review.
- Treating CAPA as paperwork for auditors rather than a learning system.