TABLE 2.
Area Under the Receiver Operating Characteristic Curve for Prediction Models on Both Derivation and Validation Cohorts
| Model | Variable | AUC (95% CI), Derivation Cohort (n = 10,085) | AUC (95% CI), Validation Cohort (n = 5,037) | Logistic Regression, OR (95% CI)a |
|---|---|---|---|---|
| SOFAb | SOFA | 0.66 (0.65–0.67) | 0.66 (0.64–0.67) | 1.39 (1.35–1.42) |
| SOFA categoriesc | ≥ 6 and < 9 | 0.55 (0.54–0.55) | 0.54 (0.54–0.55) | 3.42 (2.89–4.06) |
| ≥ 9 and < 12 | 4.73 (3–7.82) | |||
| ≥ 12 | 5.89 (1.96–25.32) | |||
| Age | Age | 0.71 (0.7–0.72) | 0.71 (0.69–0.72) | 1.06 (1.06–1.06) |
| Age + SOFA categories | Age | 0.73 (0.72–0.74) | 0.72 (0.71–0.73) | 1.06 (1.05–1.06) |
| ≥ 6 and < 9 | 3.18 (2.67–3.82) | |||
| ≥ 9 and < 12 | 4.92 (3.05–8.3) | |||
| ≥ 12 | 6.66 (2.13–29.31) | |||
| Age + SOFA | Age | 0.75 (0.74–0.76) | 0.74 (0.73–0.76) | 1.06 (1.05–1.06) |
| SOFA | 1.33 (1.3–1.36) | |||
| SOFA + age + covariatesd | SOFA | 0.75 (0.74–0.76) | 0.74 (0.73–0.76) | 1.33 (1.29–1.36) |
| Age | 1.06 (1.05–1.06) | |||
| Gender (male vs female) | 1.15 (1.05–1.25) | |||
| Obesity | 0.92 (0.79–1.08) | |||
| Diabetes | 1.18 (1.05–1.32) | |||
| Hypertension | 0.84 (0.75–0.93) | |||
| SOFA + age + Elixhauser score | Age | 0.75 (0.74–0.76) | 0.74 (0.73–0.76) | 1.06 (1.05–1.06) |
| Elixhauser score | 1 (0.97–1.03) | |||
| SOFA | 1.33 (1.3–1.36) | |||
| SOFA + Elixhauser score | SOFA | 0.66 (0.65–0.67) | 0.66 (0.65–0.68) | 1.38 (1.35–1.42) |
| Elixhauser score | 1.04 (1.01–1.07) | |||
| Categories SOFA + Elixhauser score | ≥ 6 and < 9 | 0.57 (0.56–0.58) | 0.56 (0.55–0.58) | 3.33 (2.82–3.96) |
| ≥ 9 and < 12 | 4.59 (2.91–7.59) | |||
| ≥ 12 | 5.75 (1.91–24.76) | |||
| Elixhauser score | 1.06 (1.03–1.09) |
AUC = area under the receiver operating curve, OR = odds ratio, SOFA = Sequential Organ Failure Assessment.
a
Outcome variable has two levels: deceased and discharged, where discharged is served as the reference level.
b
SOFA and all components are the scores recorded within the 24 hr prior to the start of ventilation.
c
Variable SOFA category is created based on SOFA variable with the cutoffs of: < 6, ≥ 6 and < 9, ≥ 9 and < 12, and ≥ 12. In the logistic regression model, SOFA < 6 is served as the reference group.
d
Covariates include age, gender, obesity, hypertension, and diabetes.