Figure 3.

Procalcitonin does not discriminate between the presence or absence of bacterial pneumonia in mechanically ventilated patients with suspected infection. (A) Scatter plots showing procalcitonin values in two independent prospective cohorts of mechanically ventilated patients with suspected pneumonia. Vertical lines extend from the 25th to the 75th percentiles of recorded values, and the horizontal line is plotted at the median (P > 0.05 for both cohorts). (B) Receiver operating characteristics curves of procalcitonin for the diagnosis of bacterial pneumonia. AUC = area under the curve; CI = confidence interval; ns = not significant.