Fig. 4From: Glutaminyl cyclase activity correlates with levels of Aβ peptides and mediators of angiogenesis in cerebrospinal fluid of Alzheimer’s disease patientsImprovement of diagnostic performance by addition of QC activity to logistic regression for AD prediction. Upper left: tau levels (open circles) of control (0) and AD (1) groups and logistic regression curve (red) with tau as a single parameter. Upper middle: logistic regression curve (red) calculated with tau and QC as variables and levels of combined tau–QC parameter (open circles) for control (0) and AD (1) groups. Upper right: ROC curves for results of logistic regression with tau alone (blue) or a tau–QC combination (red), p value from DeLongs test. Lower left: ptau levels (open circles) of control (0) and AD (1) groups and logistic regression curve (red) with ptau as a single parameter. Lower middle: logistic regression curve (red) calculated with ptau and QC as variables and levels of combined ptau–QC parameter (open circles) for control (0) and AD (1) groups. Lower right: ROC curves for results of logistic regression with ptau alone (blue) or a ptau–QC combination (red), p value from DeLongs test. AD Alzheimer’s disease, QC glutaminyl cyclase, ROC receiver operating characteristic (Colour figure online)Back to article page