Table 8 Diagnostic value of signs in a low prevalence population with CXR-confirmed pneumonia

From: Diagnostic value of signs, symptoms and diagnostic tests for diagnosing pneumonia in ambulant children in developed countries: a systematic review

Index test Study nr. Pneumonia prevalence Sensitivity Specificity PPV NPV
Tachypnea 5a 6.7% 74.27 42.05 8.44 95.78
6.3b 7% 77.78 60.18 13.46 97.14
Tachycardia 2 3.4% 63.04 57.36 4.91 97.80
5 6.7% 50.29 57.28 7.81 94.12
Saturation <94% 5 6.7% 13.45 97.43 27.38 93.99
6.3 7% 40.74 88.20 21.57 94.92
Wheezing 5 6.7% 15.38 93.87 8.06 96.95
4 8.6% 20.45 83.69 10.59 91.76
Crackles 5 6.7% 35.83 92.64 14.54 97.64
4 8.6% 20.45 86.48 12.50 92.01
Retractions 5 6.7% 14.62 92.51 12.32 93.77
6.3 7% 29.63 89.38 18.18 94.10
Ill appearance 4 8.6% 31.82 71.24 9.46 91.71
5 6.7% 30.99 80.01 10.04 94.16
6.3 7% 77.78 81.42 25.00 97.87
  1. aCutoff values for tachypnea: WHO definition
  2. bCutoff values for tachypnea: APLS criteria
  3. PPV positive predictive value, NPV negative predictive value