Fig. 3From: Reduced cGMP levels in CSF of AD patients correlate with severity of dementia and current depressionDiagnostic potential of cGMP as an AD biomarker. ROC curve analysis of CSF levels of cGMP in AD patients compared with control subjects. Sensitivity is defined as the fraction of those with the disease correctly identified as positive by the test. Specificity is defined as the fraction of those without the disease correctly identified as negative by the test. Youden’s index = sensitivity + specificity – 1. Likelihood ratio = sensitivity / (1 – specificity). Cut-off value for cGMP was <0.201 pmol/ml. AUC area under the curve, CI 95% confidence intervalBack to article page