Test characteristic* Any respiratory culture Tracheostomy aspirate (TA) culture Bronchoalveolar lavage (BAL) culture
Sensitivity 27.2% 28.4% 16.4%
Specificity 85.4% 81.8% 89.9%
Predictive Values Positive Predictive Value
32.9%
40.5%
8.3%
Negative Predictive Value
81.7 %
71.8%
95.1%
Likelihood Ratios Positive Likelihood Ratio
1.86
1.54
1.62
Negative Likelihood Ratio
0.85
0.88
0.93