CAPA (corrective and preventive action)

CAPA is a practical label for the linked activities used to address existing problems and reduce the likelihood of future problems. Corrective action tackles the cause of a detected nonconformity; a correction deals with its immediate effect. Preventive work anticipates potential failures through risk assessment, process improvement, and appropriate controls. In ISO 15189:2022, prevention is embedded in risk-based activities rather than treated only as a separate preventive-action procedure.

A useful CAPA record describes the problem, immediate containment, investigation, selected actions, responsibilities, deadlines, and effectiveness checks. For example, replacing a mislabeled tube is a correction; redesigning identification checks after investigating repeated labeling errors may be corrective action. Closing a form is not sufficient evidence that the underlying problem has been controlled.

For accreditation, CAPA demonstrates that the laboratory learns from failures instead of repeatedly repairing their consequences. Assessors can follow the connection between evidence, causes, actions, and outcomes. Choose an effectiveness check that tests the original failure mechanism, such as reviewing identification errors after a workflow change, and reopen the investigation if the problem persists.