Figure 4.

Decision trees to differentiate membranous lupus nephritis (MLN) from primary membranous nephropathy (PMN) obtained from the profile of IgG subclass (A) and complements (B). Selected markers are the immunofluorescence intensities for IgG1 in the mesangium (Mesan) and IgG2 and IgG4 along the glomerular capillary wall (GCW) (A) (mean accuracy of 88.0% from 10-fold cross-validation; SEM 3.3%) and those for C1q and C3 in the mesangium and C1q along the GCW (mean accuracy of 81.0% from 10-fold cross-validation; SEM 3.8%). Starting from node 0, the path of decision is determined by the immunofluorescence value of each marker in the path and the class of a patient (MLN or PMN) is determined at a terminal node. Each node shows the distribution of classes; at each terminal node, the dominant class is shown as a gray box. The class of a patient is determined as a dominant class of a terminal node at which the patient arrived according to the decision path.