What is the first action to take when two controls within a run are both greater than ±2s from the mean?

When both controls are greater than ±2 standard deviations (s) from the mean, this indicates a significant deviation from the expected performance of the assay. In this scenario, it is essential to first ensure the accuracy of the testing system before continuing with patient samples, as using unverified control data could lead to incorrect patient results.

The correct course of action involves recalibrating the testing system to restore it to an acceptable range of accuracy. Following this, it is crucial to repeat the controls to verify that the recalibration has resolved the issue and that the controls now fall within the acceptable limits. Once the quality control results are deemed acceptable, patient samples can be processed, ensuring that the entire testing process adheres to quality standards.

This approach minimizes the risk of reporting erroneous patient results and effectively addresses the issues revealed by the quality control failures. It emphasizes the importance of not only responding to control failures but also validating the performance before proceeding with patient testing.