Table 1 Sample size calculation to assess time to death and its predictors among mechanically ventilated patients in West Amhara comprehensive specialized hospitals, Ethiopia, 2022
Assumption | Variable | P(E) | Hazard ratio | Chart attrition rate | Sample size |
|---|---|---|---|---|---|
Power = 80% Z\(a\)/2=1.96 (α) = 0.05 P(w) = 0.1 | Neuromuscular blockers | 0.568 | 2.43 | 10% | 150 |
Use of vasopressors | 0.294 | 2.31 | 325 | ||
Hemodialysis | 0.524 | 1.91 | 305 | ||
Body mass index ≤ 21 kg/m2 | 0.516 | 1.83 | 355 |