Accuracy of Helicobacter pylori serology in two peptic ulcer populations and in healthy controls

Figure 1 Receiver operating characteristic (ROC) curve for different cut-off values for H pylori IgG antibodies in vagotomized or medically treated peptic ulcer patients and in community controls. Cut-off values were 200, 300, 500, 600 and at intervals of 300 for IgG values above 600 to 4800. TRP = True positive rate (sensitivity), FPR = False positive rate (1-specificity). A: Cut-off 200; B: Cut-off 300; C: Cut-off 500.