For artus® kits, how are weak positive samples identified?
FAQ ID -1500

A high CT value indicates a positive sample of correspondingly low concentration. On the basis of the CT values of an external standard, the real-time PCR instrument software calculates the amount of the sample's input DNA/RNA. However, if a CT value of a particular sample is higher than that of the last quantitation standard (QS4 or QS5) a precise quantitation of this sample may not be possible. Nevertheless, it still has to be reported as positive.