2. Comparison 1 (HFNC vs standard oxygen therapy): dichotomous data from studies not included in meta‐analysis.

Additional outcomes	HFNC n/N	Standard oxygen therapy n/N	Effect estimatea	Study
Atelectasis	2/56	5/54	RR 0.39, 95% CI 0.08 to 1.90	Yu 2017
Adverse events Ventilator‐acquired tracheobronchitis	3/264	7/263	RR 0.43, 95% CI 0.11 to 1.63	Hernandez 2016b
Adverse events Abdominal distension	3/56	0/54	RR 6.75, 95% CI 0.36 to 127.76	Yu 2017
Participant‐reported outcomes Dyspnoea (any improvement; using categorical data reported as marked improvement, slight improvement, no change, slight deterioration, marked deterioration)	65/106	31/94	RR 1.86, 95% CI 1.34 to 2.57	Frat 2015
Participant‐reported outcomes Dry mouth (data included dry mouth, nose, or throat)	18/47	30/43	RR 0.55, 95% CI 0.36 to 0.83	Vourc'h 2020 Vourc'h 2020
Participant‐reported outcomes Throat and nasal pain	1/56	7/54	RR 0.14, 95% CI 0.02 to 1.08	Yu 2017
acalculated using RevMan Web 2019

CI: confidence interval
HFNC: high‐flow nasal cannulae
N: total number of participants per group
n: number of participants who had an event
RR: risk ratio