A sample will get a QC warning (not pass the quality control) if Incubation Control 2 or Detection Control (corresponding to that specific sample) deviates more than a pre-determined value (+/- 0.3) from the median value of all samples on the plate.
QC warnings may occur due to operator error, for example, or because of the properties/quality of a specific sample. Samples with QC warnings due to operator error are always rerun at Analysis Service. Samples that get QC warnings due to sample quality/ properties are included in the data set but should be handled with care in statistical analysis.
If more than 1/6 of the samples per run get a QC warning, there is a high probability that the entire run is unreliable and should therefore be rerun.