What action must a laboratory take if it receives an unsatisfactory result in a proficiency test?

When a laboratory receives an unsatisfactory result in a proficiency test, it is essential to analyze the result in order to identify the underlying issues. Conducting a root cause analysis enables the laboratory to determine why the unsatisfactory result occurred, whether it was due to equipment malfunction, procedural errors, or operator mistakes. By finding the root cause, the laboratory can implement targeted corrective actions to address and rectify the identified issues, thus improving the accuracy and reliability of future test results.

Taking corrective action is vital for maintaining the integrity of laboratory operations and ensuring compliance with regulatory standards. It helps to restore confidence in the laboratory's testing capabilities and ensures that it can successfully meet quality assurance requirements. This proactive approach ultimately aids in preventing recurrence of the issues that led to the unsatisfactory result in the first place.

In contrast, ignoring the result or re-submitting the same tests without addressing the original problem would not resolve the underlying issues and could lead to continued inaccuracies. Changing the testing procedures without understanding the root cause may not effectively fix the problem and could lead to additional complications. Thus, a thorough investigation and corrective action are necessary steps for laboratories following unsatisfactory proficiency test results.