Frequency and duration of upper respiratory and PEF episodes
| Upper respiratory episodes | PEF episodes | |
|---|---|---|
| Mean (range) annual incidence | 3.7 (0–9.5) | 2.8 (0–10.2) |
| Mean (range) duration (days)2-150 | 9.2 (2–36) | 11.8 (2–49) |
| Shortest interval between onset of consecutive episodes (days) | 4 | 12 |
↵2-150 Duration was unknown for 12 upper respiratory episodes and nine PEF episodes as they continued after monitoring ceased.