Table 1.
Functional measurements before and after bronchodilator administration in the PFT study groups
| Characteristic | Group | Pre-BD Median (IQR) |
Post-BD Median (IQR) |
Mean delta change (95% CI) Mean % change (95% CI) |
| FEV1 | A | 1.4 (0.9–2.1) | 1.5 (2.0–2.2) | 0.07 (0.069 to 0.074) |
| 5.2 (–1.0 to 12.0) | ||||
| B | 2.3 (1.7–2.8) | 2.4 (1.8–2.9) | 0.12 (0.118 to 0.129) | |
| 5.0 (4.7 to 5.2) | ||||
| C | 2.9 (2.4–3.7) | 3.0 (2.4–3.8) | 0.1 (0.008 to 0.154) | |
| 2.9 (–5.6 to 10.6) | ||||
| FEV1 % predicted (GLI) | A | 44 (30–59) | 46 (32–61) | 1.9 (1.807 to 1.966) |
| 3.4 (3.2 to 3.6) | ||||
| B | 71 (56–84) | 75 (60–88) | 3.8 (3.6 to 3.9) | |
| 5.0 (4.7 to 5.2) | ||||
| C | 95 (87–105) | 99 (91–108) | 2.5 (1.5 to 3.5) | |
| 1.8 (0.4 to 3.3) | ||||
| FVC | A | 2.9 (2.2–3.7) | 3.0 (2.3–3.8) | 0.08 (0.074 to 0.081) |
| 3.0 (–2.3 to 9.0) | ||||
| B | 3.4 (2.8–4.1) | 3.5 (2.9–4.2) | 0.1 (0.095 to 0.109) | |
| 2.5 (2.3 to 2.7) | ||||
| C | 3.9 (3.0–4.8) | 3.9 (3.0–4.9) | 0.03 (–0.055 to 0.111) | |
| 0.1 (–7.1 to 9.0) | ||||
| FVC % predicted (GLI) | A | 72 (57–87) | 73 (60–88) | 1.8 (1.677 to 1.898) |
| 2.1 (1.9 to 2.3) | ||||
| B | 82 (71–95) | 85 (73–98) | 2.4 (2.2 to 2.6) | |
| 2.5 (2.3 to 2.7) | ||||
| C | 98 (90–107) | 99 (91–107) | 0.6 (–0.4 to 1.6) | |
| −0.3 (–1.8 to 1.1) | ||||
| FEV1/FVC | A | 0.53 (0.41–0.61) | 0.54 (0.41–0.63) | 0.01 (0.009 to 0.010) |
| 1.9 (–2.7 to 6.3) | ||||
| B | 0.69 (0.58–0.76) | 0.71 (0.60–0.78) | 0.018 (0.017 to 0.019) | |
| 2.4 (2.2 to 2.6) | ||||
| C | 0.77 (0.72–0.81) | 0.81 (0.75–0.84) | 1.6 (1.036 to 2.144) | |
| 0.1 (–1.9 to 1.9) | ||||
| FEV1/FVC % predicted (GLI) | A | 65 (50–75) | 66 (50–76) | 0.982 (0.909 to 1.055) |
| 1.0 (0.9 to 1.1) | ||||
| B | 88 (75–97) | 91 (77–99) | 2.3 (2.2 to 2.5) | |
| 2.4 (2.2 to 2.6) | ||||
| C | 97 (92–101) | 100 (95–104) | 0.1 (–0.2 to 0.4) | |
| 1.4 (0.6 to 2.3) |
A: training and testing combined sets, n=25 017; B: validation set 1 from AVAHCS, n=5854; C: validation set 2 from Cleveland Clinic, n=727.
AVAHCS, Atlanta Veteran Affairs Healthcare System in Atlanta, Georgia; BD, bronchodilator; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; GLI, Global Lung Initiative; PFT, pulmonary function test.