Table 3.
Diagnostic performance of four different group A streptococcus (GAS) assays in comparison with throat culture (n = 48)
| Performance, % (95% CI) | ||||||
|---|---|---|---|---|---|---|
| GAS positive samples, n (%) | Sensitivity | Specificity | PPV | NPV | Accuracya | |
| Throat culture | 11 (23) | |||||
| RADTs | ||||||
| StrepTop | 9 (19) | 82 (71–93) | 100 | 100 | 95 (89–100) | 96 (90–100) |
| mariPOC | 23 (48) | 100 | 68 (54–81) | 48 (34–62) | 100 | 75 (63–87) |
| NAATs | ||||||
| Simplexa | 15 (31) | 91 (83–99) | 86 (77–96) | 67 (53–80) | 97 (92–100) | 88 (78–97) |
| Illumigene | 11 (23) | 91 (83–99) | 97 (93–100) | 91 (8–99) | 97 (93–100) | 96 (90–100) |
CI confidence interval PPV positive predictive value, NPV negative predictive value, RADT rapid antigen detection test, NAAT nucleic acid amplification test
aAccuracy = the percentage of correctly classified samples