| Characteristic | Acute Cough | Responsiveness | Airway Obstruction | Responsiveness and Obstruction (GOLD or LLN) | No Responsiveness or Obstruction | Missing | |
|---|---|---|---|---|---|---|---|
| GOLDa | LLNb | ||||||
| History (day 1), No. (%) | 1,947 (100) | 240 (12) | 193 (10) | 126 (7%) | 41 (2%)c | 1,546 (79) | 0 (0) |
| Age, mean (SD), y | 50 (16) | 47 (17) | 58 (16) | 50 (17) | 58 (16) | 50 (16) | 0 (0) |
| Male, No. (%) | 770 (40) | 103 (43) | 82 (43) | 43 (34) | 18 (44) | 603 (39) | 0 (0) |
| Current smoking, No. (%) | 496 (26) | 78 (33) | 61 (32) | 48 (38) | 12 (29) | 366 (24) | 1 (0) |
| Pack-years of smoking, mean (SD), y | 8 (14) | 9 (17) | 13 (20) | 14 (21) | 18 (27) | 7 (13) | 28 (1) |
| History of cardiovascular disease, No. (%) | 171 (9) | 17 (7) | 22 (11) | 8 (6) | 3 (7) | 135 (9) | 1 (0.1) |
| Use of inhaled lung medication, No. (%) | 50 (3) | 14 (6) | 6 (3) | 3 (2) | 3 (7) | 33 (2) | 1 (0.1) |
| Asthma in parents or siblings, No. (%) | 423 (22) | 68 (28) | 37 (21) | 25 (22) | 8 (20) | 322 (21) | 187 (10) |
| Atopy or allergic disease, No. (%)d | 732 (38) | 116 (48) | 71 (40) | 52 (46) | 6 (39) | 552 (36) | 186 (10) |
| Cough before consultation, mean (SD), d | 9 (7) | 9 (7) | 9 (7) | 8 (7) | 10 (7) | 9 (7) | 32 (2) |
| Cough episodes last year, mean (SD), No. | 2 (2) | 3 (2) | 2 (2) | 2 (2) | 2 (2) | 1 (2) | 232 (12) |
| Spirometry (day 28) | |||||||
| FEV1, mean (SD), L | 3.0 (0.9) | 3.2 (1.1) | 2.1 (0.7) | 2.0 (0.8) | 2.1 (0.6) | 3.0 (0.9) | 0 (0) |
| FVC, mean (SD), L | 3.7 (1.1) | 4.0 (1.3) | 3.5 (1.1) | 3.6 (1.1) | 3.4 (1.0) | 3.7 (1.0) | 0 (0) |
| FEV1:FVC ratio, mean (SD) | 0.81 (0.11) | 0.79 (0.12) | 0.60 (0.11) | 0.57 (0.12) | 0.61 (0.08) | 0.83 (0.08) | 0 (0) |
RS = European Respiratory Society; FEV1 = forced expiratory volume in 1 second; FVC = forced vital capacity; GOLD = Global Initiative for Chronic Obstructive Lung Disease; LLN = lower limit of normal.
↵a According to the GOLD definition: FEV1:FVC less than 0.70.4
↵b According to ERS: LLN of FEV1:FVC ratio for males: −0.18 × age + 87.21 − (1.64 × 7.17), for females: −0.19 × age + 89.10 − (1.64 × 6.51).14
↵c These 41 participants are also included in the categories bronchodilator responsiveness and airway obstruction.
↵d Atopic symptoms or allergic disease = hay fever, eczema, urticaria, or history of allergic reaction.