Fig. 3From: Use of saliva to monitor meningococcal vaccine responses: proposing a threshold in saliva as surrogate of protectionReceiver operating characteristic (ROC) curve analysis: True positive rate (TPR) was plotted in the function of the false positive rate (FPR) for meningococcal serogroup A (a), C (b), W (c), and Y (d). The estimated threshold, which provided a specificity of ā„90% are shown as vertical dotted linesBack to article page