Figure 6.

Calibration and discrimination potentials of the new RF-based algorithm and traditional scoring systems in external validation. (A,B,C,D) In-hospitalization mortality. (A) SOFA score (Brier score =0.210; χ²=4.992, P=0.759; discrimination slope =0.085); (B) SAPS II score (Brier score =0.192; χ²=7.188, P=0.517; discrimination slope =0.16); (C) APACHE IV score (Brier score =0.203; χ²=249.148, P=0; discrimination slope =0.257); (D) the newly developed algorithm (Brier score =0.159; χ²=4.185, P=0.84; discrimination slope =0.32). (E,F) Mortality within 28 days after discharge. (E) 28_SAPS II score (Brier score =0.177; χ²=1.181, P=0.554; discrimination slope =0.291); (F) 28_RF score (Brier score =0.177; χ²=0.064, P=0.969; discrimination slope =0.294). (G,H) Mortality within 90 days after discharge. (G) 90_SAPS II score (Brier score =0.172; χ²=0.404, P=0.817; discrimination slope =0.302); (H) 90_RF (Brier score =0.170; χ²=0.472, P=0.79; discrimination slope =0.306). SOFA, Sequential Organ Failure Assessment; SAPS II, Simplified Acute Physiology Score II; APACHE, Acute Physiology and Chronic Health Evaluation.