Discriminative performance of mortality prediction scores in patients with COVID-19*
| Score | Calculation method | Predictors | No. (%) of admissions with complete data n = 1027 | AUC complete data (95% CI) | No. (%) of admissions after imputation n = 1027 | AUC after imputation (95% CI) |
|---|---|---|---|---|---|---|
| Lu | Points-based system | Age, CRP | 390 (37.9) | 0.71 (0.66–0.76) | 1027 (100) | 0.68 (0.65–0.71) |
| Hu | Regression-based system | Age, CRP, D-dimer, lymphocytes | 230 (22.4) | 0.78 (0.70–0.86) | 1027 (100) | 0.72 (0.68–0.76) |
| Xie | Regression-based system | Age, LDH, lymphocyte, oxygen saturation | 469 (45.6) | 0.80 (0.75–0.85) | 972 (94.6) | 0.75 (0.71–0.79) |
| ISARIC-4C | Points-based system | Age, sex, Charlson comorbidities, respiratory rate, oxygen saturation, GCS score, urea, CRP | 12 (1.2) | N/A† | 242 (23.6) | 0.78 (0.70–0.85) |
| mAPACHE | Points-based system | Age, mechanical ventilation, hematocrit, WBC, sodium, glucose, bilirubin, urea, creatinine, temperature, heart rate, respiratory rate, mean arterial blood pressure, metastatic cancer, AIDS, hepatic failure, cirrhosis, leukemia, lymphoma, immunosuppression, multiple myeloma | 348 (33.9) | 0.86 (0.83–0.90) | 976 (95.0) | 0.81 (0.78–0.85) |
| CISSS | Regression-based system | Age, mechanical ventilation, surgery, hematocrit, WBC, sodium, glucose, bilirubin, creatinine, bicarbonate, albumin, temperature, heart rate, respiratory rate, mean arterial blood pressure, metastatic cancer, AIDS, hepatic failure, cirrhosis, leukemia, lymphoma, immunosuppression, multiple myeloma | 357 (34.8) | 0.83 (0.78–0.88) | 976 (95.0) | 0.80 (0.77–0.84) |
| NEWS2 | Points-based system | Respiratory rate, oxygen saturation, systolic blood pressure, heart rate, level of consciousness/new confusion, temperature | 242 (23.6) | 0.72 (0.63–0.80) | 242 (23.6) | 0.72 (0.63–0.80) |
Note: AUC = area under the receiver operating characteristic curve, CI = confidence interval, CISS = critical illness severity scoring system, COVID-19 = coronavirus disease 2019, CRP = C-reactive protein, GCS = Glasgow Coma Scale, ISARIC-4C = ISARIC Coronavirus Clinical Characterisation Consortium 4C, mAPACHE = modified Acute Physiology and Chronic Health Evaluation, N/A = not applicable, NEWS2 = National Early Warning Score, WBC = white blood cell count.
↵* Mortality risk scores (31)– (36), (39) were calculated based on first valid measurement between emergency department triage and 24 hours after admission. We report model performance based on hospitalizations with complete data for all inputs and after mean imputation of missing laboratory test results (see Appendix 1 for details). We did not impute missing vital signs or mental/neurologic status data because we did not think it was reasonable to assume these values would be normal. The mortality rate in the 242 hospitalizations on which ISARIC-4C and NEWS2 scores were validated was 17.4% (42 deaths).
↵† Insufficient sample to calculate.