Results comparing mean z-scores | Results comparing mean percentage abnormal* | ||
Mean z-score FEFR75 | % with abnormal FEFR75 | ||
HFO | CV | HFO | CV |
−0.97 | −1.19 | 22% | 30% |
Difference in mean z-score: | Difference in %: | ||
0.23 (95% CI 0.02 to 0.45) | 8.2% (95% CI 0.05% to 16%) |
*Difference in % with abnormal FEF75 and its 95% CIs were calculated using a distributional approach that retains statistical power.14–18
FEF75, Forced Expiratory Flow (75% of forced vital capacity).