Cox's proportional hazards model for survival
| Hazard ratio | p‐value | 95% CI | |
| Spikes | 0.99 | 0.98 | 0.30–3.24 |
| Age | 1.04 | 0.04 | 1.00–1.08 |
| Sex | 0.85 | 0.75 | 0.30–2.40 |
| Peak Flow | 1.00 | 0.64 | 0.99–1.00 |
| Mean inspiratory pressure % | 0.98 | 0.33 | 0.95–1.02 |
| VC % | 0.98 | 0.15 | 0.96–1.01 |
CI: confidence interval
VC: vital capacity