ROC curve analysis using plasma microRNAs for discriminating endometriosis. ROC curve analyses revealed that the plasma levels of miR-17-5p, miR-20a and miR-22 were useful biomarkers for differentiating women with and without endometriosis, with AUC values of 0.74 (95% CI: 0.58–0.90), 0.79 (95% CI: 0.65–0.93) and 0.85 (95% CI: 0.71–0.98), respectively. When the three microRNAs were combined by multiplication, the AUC values for differentiating women with and without endometriosis were 0.79 (95% CI: 0.65–0.93), 0.87 (95% CI: 0.74–0.99), 0.88 (95% CI: 0.76–1.00) and 0.90 (95% CI: 0.80–1.00), respectively.