Fig.3- Receiver operating characteristic (ROC) curves for the Th17/Treg ratio, acute physiology and chronic health evaluation (APACHE) II, sequential organ failure assessment (SOFA) and Th17/Treg ratio in combination with APACHE II score, Th17/Treg ratio in combination with SOFA score for predicting sepsis patients more than 14-day ICU stay time. The area under the curve (AUC) demonstrates that the Th17/Treg ratio measures 0.747 (95% CI 0.618 to 0.850), the APACHE II score was 0.760 (95% CI 0.633 to 0.861), the SOFA score measures 0.764 (95% CI 0.637 to 0.864), PCT measures 0.627 (95% CI 0.493 to 0.749), the Th17/Treg ratio in combination with the SOFA score measures 0.782 (95% CI 0.656 to 0.878), and the Th17/Treg ratio in combination with the APACHE II score measures 0.800 (95% CI 0.676 to 0.892).