Skip to main content

Table 2 Technical features of the rapid PCR test

From: Routine use of Staphylococcus aureus rapid diagnostic test in patients with suspected ventilator-associated pneumonia

All patients Se (%)
[95% CI]
Sp (%)
[95% CI]
PPV (%)
[95% CI]
NPV (%)
[95% CI]
LR + LR - Youden index
MSSA
(Rapid PCR)
95.8
[78.9 to 99.9]
83.2
[78.9 to 86.9]
27.7
[18.4 to 38.6]
99.7
[98.1 to 99.9]
5.7 0.05 0.79
MSSA*
(Rapid PCR)
96.3
[81.0 to 99.9]
75.2
[70.6 to 79.4]
21.0
[14.2 to 29.2]
99.7
[98.1 to 99.9]
3.9 0.05 0.72
MSSA
(Rapid PCR)
85.2
[66.3 to 95.8]
84.8
[80.9 to 88.2]
27.1
[18.5 to 38.6]
98.8
[97.0 to 99.7]
5.6 0.18 0.70
MSSA (Gram stain) 62.9
[42.4 to 80.6]
80.7
[76.5 to 84.5]
18.3
[11.0 to 27.7]
97.0
[94.5 to 98.5]
3.3 0.5 0.44
MRSA
(Rapid PCR)
80.0
[28.4 to 99.5]
99.5
[98.3 to 99.9]
66.7
[22.3 to 95.7]
99.8
[98.7 to 99.9]
166.8 0.2 0.79
MRSA*
(Rapid PCR)
100.0
[47.8 to 100.0]
71.5
[66.9 to 75.8]
4.0
[1.3 to 9.2]
100.0
[98.7 to 100.0]
3.5 0.00 0.72
MRSA
(Rapid PCR)
100.0
[47.8 to 100.0]
80.3
[77.2 to 84.9]
6.0
[2.0 to 13.5]
100.0
[98.9 to 100.0]
5.3 0.00 0.81
MRSA
(Gram stain)
40.0
[5.3 to 85.3]
78.2
[73.9 to 82.1]
2.2
[0.3 to 7.6]
99.1
[97.4 to 99.8]
1.8 0.8 0.18
≥ One risk factor Se (%) Sp (%) PPV (%) NPV (%) LR + LR - Youden index
MRSA 80
[28.4 to 99.5]
99.3
[97.6 to 99.9]
66.7
[22.3 to 95.7]
99.7
[98.1 to 99.9]
118.4 0.2 0.79
  1. *Including inconclusive tests as positive; Including inconclusive test as negative
  2. Technical characteristics of the rapid PCR test and Gram stain performed on bronchoalveolar lavage samples in all patients and those with at least one risk factor for methicillin resistant Staphylococcus aureus infection
  3. LR, likelihood ratio; MRSA, methicillin-resistant Staphylococcus aureus; MSSA, methicillin-susceptible Staphylococcus aureus; NPV, negative predictive value; PPV, predictive positive value; Se, sensitivity; Sp, specificity