Table 3 sample size calculations for a definitive cRCT.
Study outcome (% or mean) | Relative risk/effect sizes SD | Absolute difference | Clusters per arm (sample size per arm) | |
|---|---|---|---|---|
Healthcare associated infection | 11.8% | 0.8 | 2.4% | 434 (82,460) |
11.8% | 0.6 | 4.4% | 120 (22,800) | |
Any positive microbiology result | 59.7% | 0.8 | 11.9% | 53 (10,070) |
59.7% | 0.6 | 23.9% | 13 (2,470) | |
Duration of invasive ventilation (days) | 7.6 | 0.2 SD | 1.6 | 12 (2,280) |
7.6 | 0.3 SD | 2.4 | 5 (950) | |
Days alive and free of mechanical ventilation at 28 days | 19.5 | 0.2 SD | 1.6 | 12 (2,280) |
19.5 | 0.3 SD | 2.4 | 5 (950) | |
Length of PICU stay (days) | 10.1 | 0.2 SD | 2.0 | 12 (2,280) |
10.1 | 0.3 SD | 3.2 | 5 (950) | |
Length of hospital stay (days) | 23.3 | 0.2 SD | 5.4 | 8 (1,520) |
23.3 | 0.3 SD | 8.1 | 4 (760) | |
PICU mortality | 7.3% | 0.8 | 1.5% | 290 (55,100) |
7.3% | 0.6 | 2.9% | 70 (13,300) | |
Hospital mortality | 9.4% | 0.8 | 1.9% | 179 (34,010) |
9.4% | 0.6 | 3.8% | 40 (7,600) | |
30-day mortality | 7.7% | 0.8 | 1.54 | 182 (34,580) |
7.7% | 0.6 | 3.1% | 38 (7,220) |
