Number of Centor criteria by streptococcal groups in 306 patients with sore throat by streptococcal culture, southern Norway 2000–2002.
| GAS | C or G | Culture -ve | Total | GAS | C or G | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| Clinical features | n= 127n (%) | n= 33n (%) | n= 146n (%) | n= 306n (%) | Sens | Spec | LR | Sens | Spes | LR |
| Four Centor criteria | 19 (15) | 4 (12) | 14 (10) | 37 (12) | 0.15 | 0.90 | 1.5 | 0.12 | 0.90 | 1.2 |
| Three Centor criteria | 42 (33) | 11 (33) | 33 (23) | 86 (29) | 0.33 | 0.77 | 1.4 | 0.33 | 0.77 | 1.4 |
| Two Centor criteria | 46 (37) | 10 (30) | 46 (33) | 102 (34) | 0.37 | 0.67 | 1.1 | 0.30 | 0.67 | 0.9 |
| One Centor criterion | 15 (12) | 7 (21) | 31 (22) | 53 (12) | 0.12 | 0.78 | 0.6 | 0.21 | 0.78 | 1.0 |
| Zero Centor criteria | 4 (3) | 1 (3) | 17 (12) | 22 (7) | 0.03 | 0.88 | 0.3 | 0.03 | 0.88 | 0.3 |
| Three or more Centor criteria | 61 (48)a | 15 (45) | 47 (33) | 123 (41) | 0.48 | 0.67 | 1.5 | 0.45 | 0.67 | 1.4 |
| Two or more Centor criteria | 107 (85)a | 25 (75) | 93 (66) | 225 (75) | 0.85 | 0.34 | 1.3 | 0.75 | 0.34 | 1.1 |
↵a P<0.05 in bivariate analysis of GAS vs group with no bacteria. GAS = group A streptococci. Sens = sensitivity. Spec = specificity. LR = likelihood ratio.