Table 2. Development of Zurich Donor Score based on estimated β-coefficients from multiple Cox model and shrinked coefficients.
| Predictor | N | HR (95% CI) | β | Shrinked β | Score points Zurich donor score (total 17 points) |
|---|---|---|---|---|---|
| Significant pulmonary infection* | |||||
| Yes | 127 | 1.46 (1.14–1.87) | 0.38 | 0.31 | 3 |
| No | 327 | – | – | – | 0 |
| Diabetes mellitus | |||||
| Yes | 25 | 1.29 (0.80–2.10) | 0.25 | 0.21 | 2 |
| No | 429 | – | – | – | 0 |
| PaO2/FiO2-ratio (mmHg) | |||||
| >300 | 278 | – | – | – | 0 |
| 300 to >150 | 134 | 1.30 (1.01–1.66) | 0.26 | 0.21 | 2 |
| ≤150 | 42 | 1.50 (1.22–1.87) | 0.4 | 0.33 | 3 |
| Smoking history (pack years) | |||||
| <20 | 377 | – | – | – | 0 |
| 20 to <50 | 69 | 1.43 (0.60–3.50) | 0.36 | 0.29 | 3 |
| ≥50 | 8 | 1.63 (1.22–2.18) | 0.49 | 0.4 | 4 |
| Age (years) | |||||
| <50 | 273 | – | – | – | 0 |
| 50 to <70 | 151 | 1.31 (1.02–1.68) | 0.27 | 0.22 | 2 |
| ≥70 | 30 | 2.24 (1.44–3.50) | 0.81 | 0.66 | 5 |
β, β-coefficient; CI, confidence interval; HR, hazard ratio. *Radiological suspicion of pneumonia, bronchoscopic sign of severe bronchitis, history of aspiration (radiological suspicion of pneumonia: opacity in one or more lobes not predominantly resembling in morphology to atelectasis or edema; Signs of severe bronchitis: purulent secretions and/or signs of bronchial inflammation in bronchoscopy; History of aspiration: observed aspiration, signs in bronchoscopy of aspiration or a history highly suspicious of aspiration).