Clinical characteristics of control subjects
| Subject no. | Age | Sex | Smoking habits | Allergy/atopy | FEV1 % pred | PD20 µg |
| 1 | 38 | M | O | None | 90.3 | >2340 |
| 2 | 25 | M | O | None | 101.8 | >2340 |
| 3 | 21 | F | C# | None | 95.1 | >2340 |
| 4 | 28 | M | C¶ | None | 99.4 | >2340 |
| 5 | 26 | F | None | None | 103.6 | >2340 |
| 6 | 23 | F | None | None | 113.1 | >2340 |
| 7 | 24 | F | None | None | 102.2 | >2340 |
FEV1: forced expiratory volume in one second
PD20: provocation dose causing a 20% fall in FEV1
M: male
F: female
O: occasional smoker
C: current smoker
#: 10
and ¶·: 15 cigarettesday−1