Table 2.
Summary estimates of sensitivity, specificity, positive likelihood ratio (LR) and negative LR calculated for signs and symptoms using a bivariate random effects model
| Sign or symptom | No. of studies | No. of patients | Sensitivity (95% CI) | Specificity (95% CI) | +LR (95% CI) | -LR (95% CI) |
|---|---|---|---|---|---|---|
| Absence of cough | 19 | 4,653 | 0.74 (0.68 to 0.79) | 0.49 (0.40 to 0.58) | 1.46 (1.28 to 1.66) | 0.53 (0.46 to 0.61) |
| Fevera | 21 | 4,635 | 0.50 (0.39 to 0.62) | 0.70 (0.58 to 0.79) | 1.65 (1.40 to 1.95) | 0.71 (0.64 to 0.80) |
| Anterior cervical adenopathyb | 9 | 2,101 | 0.65 (0.55 to 0.74) | 0.55 (0.45 to 0.64) | 1.45 (1.25 to 1.67) | 0.63 (0.52 to 0.76) |
| Tender anterior cervical adenopathyb | 16 | 4,144 | 0.67 (0.52 to 0.79) | 0.59 (0.49 to 0.69) | 1.65 (1.41 to 1.92) | 0.56 (0.41 to 0.76) |
| Any exudatesc | 21 | 4,839 | 0.57 (0.44 to 0.70) | 0.74 (0.63 to 0.82) | 2.20 (1.76 to 2.74) | 0.58 (0.47 to 0.72) |
aThe most widely used cut-off point to indicate fever was 38.0°C. Studies also used 37.5°C [40], 37.8°C [37,44,46], 38.3°C [13], 38.5°C [31,45].
bStudies reported on tender lymph nodes, adenopathy or tender adenopathy. All adenopathy results were categorised into tender anterior cervical adenopathy or anterior cervical adenopathy.
cIncludes results for 'tonsillar exudate', 'pharyngeal exudate' and 'exudate'. If both tonsillar and pharyngeal exudate were reported only the results for tonsillar exudate were added to avoid double counting.