Fig. 1
From: Low neutrophil-to-lymphocyte ratio identifies secondary polycythemia in patients with erythrocytosis

Diagnostic performance of NLR and EPO in distinguishing PV from SP. Receiver operating characteristic (ROC) curves show that the neutrophil-to-lymphocyte ratio (NLR) had superior diagnostic accuracy compared to serum erythropoietin (EPO) levels (AUC 0.919 vs. 0.835, p < 0.001). The combination of NLR and EPO further improved the area under the curve (AUC 0.955).