Table 3.
Clinical Finding | Sensitivity | Specificity | Positive predictive value |
Negative predictive value |
Treatment ratio‡ |
---|---|---|---|---|---|
Individual signs | |||||
Tender cervical lymph nodes (LN) | 89.8 | 28.2 | 30.0 | 88.9 | 3.0 |
Tonsillar hypertrophy | 74.4 | 41.7 | 30.4 | 82.6 | 2.8 |
Uvular erythema | 35.4 | 72.3 | 30.5 | 76.6 | 3.3 |
Tonsillar exudate | 33.9 | 86.9 | 47.1 | 79.3 | 3.2 |
Chills | 28.7 | 86.9 | 27.9 | 75.3 | 3.6 |
Cough | 39.4 | 51.1 | 21.7 | 71.1 | 2.6 |
Malaise | 37.4 | 58.3 | 23.5 | 73.1 | 2.3 |
Hoarseness | 22.9 | 71.4 | 21.5 | 73.0 | 2.6 |
Combinations of signs | |||||
Either tender cervical LN or tonsillar exudate | 92.9 | 26.8 | 30.3 | 91.6 | 2.3 |
≥1 of 3 findings* | 95.5 | 17.2 | 28.3 | 91.8 | 2.5 |
≥1 of 5 findings** | 96.4 | 10.8 | 27.0 | 89.8 | 2.7 |
≥2 of 5 findings** | 84.0 | 35.7 | 30.9 | 86.7 | 2.2 |
Either tender cervical LN or tonsillar exudate, and either cough, hoarseness, or malaise | 65.3 | 56.4 | 33.9 | 82.6 | 2.5 |
≥ 1 of 3 findings* and ≤ 2 of: cough, hoarseness, malaise | 67.5 | 48.1 | 30.8 | 81.2 | 2.4 |
≥ 1 of 3 findings* and no cough | 88.2 | 28.0 | 29.6 | 87.4 | 2.0 |
≥ 1 of 3 findings* and no hoarseness | 58.4 | 59.1 | 32.8 | 80.5 | 2.3 |
≥ 1 of 3 findings* and no malaise | 73.1 | 42.3 | 30.3 | 82.1 | 2.3 |
3 findings denotes: tender cervical LN, tonsillar exudate, or tonsillar hypertrophy
5 findings denotes: tender cervical LN, tonsillar exudate, tonsillar hypertrophy, chills, or uvular erythema
Based on the presence of the clinical finding, the number of GAS-negative episodes that would be treated for every GAS-positive episode treated