Figure 1.
Receiver Operating Curves (ROC) characteristics of the diagnostic performance of copeptin for severe P. falciparum malaria, compared to that of sodium, lactate, CRP and procalcitonin. The ROC curve is a graph of sensitivity (true positive fraction) plotted against 1-specificity (false positive fraction). The performance of a diagnostic variable can be quantified by calculating the area under the ROC curve (AUROC). The ideal test would have an AUROC of 1, whereas a random guess would have an AUROC of 0.5. The results of the pair-wise comparison of ROC curves are shown (with copeptin ROC curve as comparator). a. copeptin vs sodium (n = 204 pairs, p-value not significant); b. copeptin vs lactate (n = 124 pairs, p-value not significant); c. copeptin vs CRP (n = 202 pairs, p = 0.02); d. copeptin vs procalcitonin (n = 70 pairs, p-value not significant). The copeptin graphs are not all identical due to missing values in pair-wise comparisons.