Table 3.
Results from multivariable analysis according to different models.
| Model 1 | Model 2 | Model 3 | Model 4 | |
|---|---|---|---|---|
| RR (95%CI) | RR (95%CI) | RR (95%CI) | RR (95%CI) | |
| Δ% ABG | ||||
| PaO2 | 0.997 (0.995−0.999) | Not entered | Not entered | Not entered |
| SpO2 | Not entered | 0.989 (0.981−0.998) | Not entered | Not entered |
| FiO2 | 1.003 (1.001−1.005) | 1.002 (1.000−1.005) | Not entered | Not entered |
| Lactate | 1.000 (0.997−1.003) | 1.000 (0.997−1.003) | 1.000 (0.997−1.003) | 1.000 (0.997−1.003) |
| PaO2/FiO2 | Not entered | Not entered | 0.998 (0.996−0.999) | Not entered |
| SpO2/FiO2 | Not entered | Not entered | Not entered | 0.997 (0.995−1.000) |
| Demographic and clinical characteristics | ||||
| Age | 1.026 (1.008−1.044) | 1.025 (1.007−1.044) | 1.026 (1.009−1.044) | 1.025 (1.007−1.044) |
| Males vs Females | 1.732 (1.088−2.757) | 1.794 (1.124−2.864) | 1.718 (1.094−2.699) | 1.750 (1.117−2.742) |
| Charlson comorbidity index | 0.987 (0.896−1.087) | 1.010 (0.916−1.114) | 0.981 (0.894−1.077) | 0.992 (0.905−1.087) |
| Lactate dehydrogenase | 1.000 (1.000−1.001) | 1.001 (1.000−1.001) | 1.001 (1.000−1.001) | 1.001 (1.000−1.001) |
| C-reactive protein | 1.011 (0.990−1.033) | 1.020 (0.999−1.042) | 1.013 (0.991−1.035) | 1.020 (0.999−1.042) |
| White blood cell count | 1.014 (0.960−1.071) | 1.005 (0.950−1.063) | 1.014 (0.959−1.072) | 1.004 (0.949−1.063) |
| Lymphocyte count | 0.833 (0.594−1.167) | 0.835 (0.545−1.281) | 0.843 (0.613−1.159) | 0.849 (0.565−1.274) |
| C-index (95%CI) | 0.818 (0.771−0.906) | 0.792 (0.769 – 0.883) | 0.818 (0.753−0.883) | 0.791 (0.775−0.897) |
ABG arterial blood gas, PaO2 partial pressure of oxygen, SpO2 oxygen saturation, FiO2 inspired oxygen fraction, RR relative risk, CI confidence interval. All models are adjusted by centre.