Method | Protocol | Positivity criteria |
Bronchodilatation test | FEV1 before and 15 min after inhalation of a standard β2-agonist | FEV1 increase from baseline ≥200 mL and ≥12% of predicted |
Bronchial provocation challenges | ||
Methacholine test | Provocative dose (PD20) or concentration (PC20) of inhaled methacholine inducing an FEV1 decrease from baseline ≥20% | PC20 ≤4 mg·mL−1 or PD20 ≤400 μg (cumulative dose), or ≤200 μg (noncumulative dose) in those not taking ICS PC20 ≤16 mg·mL−1 or PD20 ≤1,600 μg (cumulative dose) or ≤800 μg (noncumulative dose) in those taking ICS for at least 1 month |
Eucapnic voluntary hyperpnoea | FEV1 before and within 30 min of 6 min dry (or dry and cool) air inhalation at 85% of predicted maximum voluntary ventilation | ≥10% decrease in FEV1 from baseline |
Hypertonic saline inhalation | FEV1 before and after inhaling 22.5 mL of 4.5% NaCl | ≥15% decrease in FEV1 from baseline |
Mannitol inhalation | Provocative dose of inhaled mannitol inducing FEV1 decrease from baseline ≥15% (PD15M) | PD15M ≤635 mg of mannitol |
Exercise challenge (field or laboratory) | FEV1 before and within 30 min after exercise challenge achieving a heart rate >85% for at least 4 min | ≥10% decrease in FEV1 from baseline |
FEV1: forced expiratory volume in 1 s; ICS: inhaled corticosteroids.