Wall thickness to bronchial diameter(T/D) and wall area (WA%) in small and large airways
| Group 1 | Group 2 | Group 3 | Group 4 | |
|---|---|---|---|---|
| Small airways ⩽2 mm | ||||
| n | 141 | 159 | 117 | 95 |
| Mean (SD) T/D ratio3-150 | 0.3.0 (0.04) | 0.30 (0.04) | 0.28 (0.03) | 0.26 (0.03) |
| Mean (SD) WA%3-150 | 84.0 (5.8) | 83.8 (5.7) | 79.8 (4.5) | 78.2 (4.9) |
| Large airways >2 mm | ||||
| n | 147 | 107 | 129 | 166 |
| Mean (SD) T/D ratio3-150 | 0.24 (0.04) | 0.24 (0.04) | 0.22 (0.02) | 0.21 (0.03) |
| Mean (SD) WA%3-150 | 72.2 (8.2) | 71.5 (8.4) | 69.1 (5.9) | 66.8 (6.7) |
↵3-150 There was no significant difference between groups 1 and 2, but both groups were significantly greater than either group 3 or 4 (p < 0.001), and group 3 was significantly greater than group 4 (p < 0.05).