Table 3.
Interpretation and Purpose of Controls for Two- and One-Step Singleplex Assays
| Control Type | Control Name | Used to Monitor/Where to Repeat Protocol | Expected Results |
Expected CT Values | ||
|---|---|---|---|---|---|---|
| N1 | N2 | RP | ||||
| Negative | NTC | contamination during qRT-PCR process | − | − | − | undetected |
| Positive | SARS-CoV-2 RNA | amplification/primer-probe integrity | + | + | − | <40 (N1, N2,) and undetected (RP) |
| Extraction | POS EC | extraction/sample stability | + | + | + | <40 (N1, N2, RP) |
| NEG EC | extraction cross-contamination | − | − | + | undetected (N1, N2) and <40 (RP) | |
| human RP gene | extraction/amplification/sample stability | NA | NA | + | <40 (RP) | |