Table E1.
Anti-RBD and anti-N antibody quality controls and variation coefficients
| Controls | Statistical parameters | Anti-RBD |
Anti-N |
||
|---|---|---|---|---|---|
| Date | Value (U/mL) | Date | Value (COI) | ||
| Internal positive quality controls∗ | 12.10.2020 | 4.79 | 12.10.2020 | 3.07 | |
| 13.10.2020 | 4.85 | 13.10.2020 | 3.01 | ||
| 14.10.2020 | 4.78 | 14.10.2020 | 3.04 | ||
| 15.10.2020 | 4.74 | 15.10.2020 | 3.06 | ||
| Mean | 4.79 | 3.05 | |||
| SD | 0.05 | 0.03 | |||
| Intralot variation coefficient | 0.95% | 0.87% | |||
| External positive quality controls† | 12.10.2020 | 9.08 | 12.10.2020 | 2.72 | |
| 13.10.2020 | 9.16 | 13.10.2020 | 2.74 | ||
| 14.10.2020 | 8.87 | 14.10.2020 | 2.75 | ||
| 15.10.2020 | 8.98 | 15.10.2020 | 2.76 | ||
| Mean | 9.02 | 2.74 | |||
| SD | 0.13 | 0.02 | |||
| Intralot variation coefficient | 1.39% | 0.62% | |||
| External negative quality controls | 12.10.2020 | <0.4 | 12.10.2020 | 0.09 | |
| 13.10.2020 | <0.4 | 13.10.2020 | 0.09 | ||
| 14.10.2020 | <0.4 | 14.10.2020 | 0.10 | ||
| 15.10.2020 | <0.4 | 15.10.2020 | 0.10 | ||
| Mean | — | 0.09 | |||
| SD | — | 0.00331 | |||
| Intralot variation coefficient | — | 3.49% | |||
COI, Cutoff index; N, nucleoprotein.
∗
In-house diluted leftover serum sample with high antibody levels, allowing for interlot and intralot comparison (determination of the coefficient of variation).
†
Manufacturer’s positive and negative quality controls (Roche SARS-Cov2 S PreciControl) that need to be respectively between 7.21 and 13.4 U/mL and below 0.4 U/mL, for the run to be carried out.