Primary and key secondary outcomes
| High flow | Conventional | P value | |||
| Nasal oxygen | Oxygen therapy | Difference* | Risk ratio | ||
| (n=181) | (n=181) | (95% CI) | (95% CI) | ||
| Primary outcome | |||||
| Escalation of respiratory support, No. (%) | 55 (30.3) | 70 (38.6) | 0.0973 | −8.29 (−18.05 to 1.47) | 0.79 (0.59 to 1.05) |
| Secondary outcomes | |||||
| Clinical recovery, No. (%) | 125 (69.1) | 110 (60.8) | 0.0985 | 8.29 (−1.51 to 18.08) | 1.14 (0.98 to 1.32) |
| Time to first escalation of respiratory support (for patients with escalation), median (IQR) | 2 (1–3) | 2 (1–3) | 0.8904 | −0.28 (−1.26 to 0.70) | – |
| First treatment for escalation of respiratory support, No. (% on escalation) | 0.7467 | ||||
| CPAP | 29 (52.7) | 39 (55.7) | −2.99 (−20.58 to 14.61) | 0.95 (0.68 to 1.31) | |
| NIV | 22 (40.0) | 24 (34.3) | 5.71 (−11.35 to 22.78) | 1.17 (0.73 to 1.84) | |
| IMV | 4 (7.3) | 7 (10.0) | −2.73 (−12.55 to 7.10) | 0.73 (0.22 to 2.36) | |
| ICU admission, No. (%) | 14 (7.7) | 20 (11.0) | 0.2797 | −3.31 (−9.32 to 2.69) | 0.70 (0.37 to 1.34) |
| Length of stay in hospital,† median (IQR) | 11 (8–17) | 11 (7–20) | 0.9872 | −0.99 (−3.16 to 1.17) | – |
| Deaths within 28 days, No. (%) | 14 (7.7) | 13 (7.2) | 0.8414 | 0.55 (−4.86 to 5.96) | 1.08 (0.52 to 2.23) |
| Deaths within 60 days, No. (%) | 15 (8.3) | 15 (8.3) | 1.0000 | 0.00 (−5.68 to 5.68) | 1.00 (0.50 to 1.98) |
* Absolute risk difference (%) for binary outcomes; mean difference for continuous outcomes.
† Two patients (0.6% of study population) were still hospitalised after 60 days from hospital admission.
CPAP, continuous positive airway pressure; ICU, intensive care unit; IMV, invasive mechanical ventilation; NIV, non-invasive ventilation.