Quartiles of the ELISA index distribution among controls
| Antigen | Lower quartile | Median | Upper quartile | Cutoff |
|---|---|---|---|---|
| Dutch strains | 0.62 | 0.90 | 1.05 | 0.65 |
| Venezuelan strains | 0.49 | 0.83 | 1.05 | 0.21 |
| French strains | 0.39 | 0.77 | 1.09 | 0.21 |
| Commercial kit | 95.5 | 275.5 | >300a | 20 |
a Upper quartile is not known because values >300 are censored.