Table 2.
Comparison between % predicted FEV1 and % predicted PEFR in each category of airflow limitation
| Category of airflow limitation (%) | % predicted FEV1 | % predicted PEFR | % FEV1−% PEFR mean difference (95% CI) | P-value |
|---|---|---|---|---|
| ≥80 (n=30) | 90.8±15.9 | 82.9±17.6 | 7.9 (−0.6, 16.4) | 0.068 |
| 50–<80 (n=114) | 61.9±8.3 | 62.2±17.3 | −0.3 (−3.1, 2.6) | 0.855 |
| 30–<50 (n=116) | 39.9±5.5 | 42.7±11.9 | −2.7 (−4.7, −0.8) | 0.007 |
| 0–<30 (n=40) | 25.0±4.3 | 29.3±9.5 | −4.3 (−7.3, −1.3) | 0.006 |
| All categories (n=300) | 51.4±20.1 | 52.3±21.1 | −0.9 (−2.6, 0.7) | 0.076 |
Notes: Data are presented in mean ± standard deviation, confidence interval (CI). Bold text denotes statistical significance.
Abbreviations: FEV1, forced expiratory volume in 1 second; PEFR, peak expiratory flow rate.