Personal characteristics, exposure | Cases (n=5) | Non-cases (n=15) | RR | CI | p Value | |
---|---|---|---|---|---|---|
Sex | Male | 3 (60%) | 7 (47%) | 1.5 | 0.2 to 18.0 | 1.00 |
Multiples | Yes/no | 0 (0%) | 2 (13%) | 1.3 | 0.0 to 9.82 | 1.00 |
Birth weight (g) | Median (range) | 1800 (498–3000) | 2300 (613–4210) | 1.0 | 1.0 to 1.0 | 0.50 |
Gestational age (weeks+days) | Median (range) | 31+2 (24+2–36+3) | 34+2 (24+1–42+1) | 0.9 | 0.7 to 1.1 | 0.21 |
Central venous catheter | Yes | 4 (80%) | 6 (40%) | 4.0 | 0.4 to 197.0 | 0.38 |
Umbilical catheter | Yes | 4 (80%) | 2 (13%) | 9.3 | 0.9 to 459.6 | 0.06 |
Arterial catheter | Yes | 3 (60%) | 0 (0%) | 8.5 | 1.0 to 101.8 | 0.05 |
Mechanical ventilation | Yes | 3 (60%) | 4 (27%) | 2.8 | 0.3 to 33.4 | 0.47 |
Surfactant | Yes | 3 (60%) | 2 (13%) | 4.5 | 0.5 to 53.9 | 0.21 |
‘Frequent manipulation’ (0–10)* | Median (range) | 7 (4–10) | 4 (0–7) | 1.4 | 1.0 to 2.2 | 0.04 |
Univariable exact Poisson regression and corresponding 95% CI.
*Combined variables as proxy for ‘frequent manipulation’ (administration of eye drops (1)+continuous positive airway pressure (1)+radiograph (1)+ECG (1)+physiotherapy (1)+umbilical catheter (1)+central venous catheter (1)+arterial catheter (1)+urinary catheter (1)+administration of surfactant (1)+mechanical ventilation (1)+blood transfusion (1)).