Characteristics of the patients at randomisation in the intent-to-treat population and primary and secondary outcomes
| Total | Synchronous first | Asynchronous first | |
| Patients, n | 26 | 14 | 12 |
| Patient characteristics | |||
| Gender, n (%) | |||
| Male | 19 (73) | 11 (79) | 8 (67) |
| Female | 7 (27) | 3 (21) | 4 (33) |
| Age (years) | 55 (18), 35–81 | 55 (18), 38–81 | 56.5 (16.75), 35–73 |
| MoCA | 27 (3), 25–30 | 27.5 (1.75), 25–30 | 27 (4.24), 25–30 |
| SpO2 on oxygen therapy# | 94 (4.3), 90–98 | 95 (5.5), 90–98 | 92.5 (4), 91–96 |
| Oxygen flow (L·min−1)# | 1 (3), 0–8 | 2 (2), 0–8 | 0.25 (1.75), 0–4 |
| Heart rate (beats·min−1)# | 74.5 (22), 52–108 | 79.5 (24.5), 62–108 | 70.5 (11.5), 62–92 |
| Days since first symptom onset# | 17 (22), 3–39 | 14 (21), 3–39 | 18.5 (16.25), 6–37 |
| Contagious at time of testing, n (%) | 16 (62) | 10 (71) | 7 (58) |
| Primary outcomes | |||
| Breathing comfort | 1 (2), −3–2 | 0 (2), −3–2 | 1 (3.25), −2–2 |
| Breathing difficulty | 1 (3), −3–2 | 1 (3), −3–2 | 0 (3.25), −3–2 |
| Secondary outcomes | |||
| Respiratory rate (breaths·min−1) | 21 (10), 7–35 | 21 (10), 15–32 | 22 (10), 15–35 |
| Respiratory rate variability (breaths·min−1) | 3 (2), 1–12 | 3 (2), 1–12 | 3 (2), 1–5 |
Data are presented as median (IQR), range, unless otherwise stated. MoCA: Montreal Cognitive Assessment; SpO2: peripheral oxygen saturation; IQR: interquartile range. #: data were missing for some patients and the denominator in the asynchronous group was 10.