Demographic and clinical data for patient and control groups
| Serial tracheostomy (n=9) | Long-term tracheostomy (n=24) | Bronchoscopy controls (n=13) | |
| Median age at enrolment, months (IQR) | 4 (2–10) | 35 (14–54) | 28 (13–40) |
| Percentage male (%) | 67 | 71 | 53 |
| Percentage premature <38 weeks (%) | 56 | 54 | 31 |
| Median weight in kilograms at enrolment (IQR) | 5 (4–7) | 13 (10–16) | 13 (9–15) |
| Caesarean section delivery (%) | 33 | 29 | 46 |
| Non-oral feeding route (%) | 100 | 63 | 15 |
| Antibiotics prescribed in the year prior to enrolment (%) | 100 | 83 | 31 |