Selected studies of bronchodilator response
| Population | Agent/mode of delivery | FVC | FEV1 | MEF25–75% or MEF50% | Comments |
| Selected population studies | |||||
| 1063 subjects 8–75 yrs of age; general population 108 | IP 2 puffs via MDI | 10.7% (0.40 L) | 7.7% (0.31 L) | 20% | 95th percentile for per cent change from baseline |
| 2609 subjects; random sample of 3 areas in Alberta, Canada 109 | TB 500 µg via spacer | Males 9% (0.34 L); females 9% (0.22 L) | 95th percentile for per cent change from baseline in asymptomatic never-smokers with FEV1 >80% pred | ||
| 75 selected normal subjects 110 | Two puffs via MDI | 5.1% (0.23 L) | 10.1% (0.36 L) | 48.3% | Upper 95% CL (two-tailed) for per cent change from baseline |
| Selected patient studies | |||||
| 40 patients referred to PFT laboratory 112 | Placebo | 14.9% (0.34 L) | 12.3% (0.18 L) | 45.1% | Upper 95% CI change after placebo |
| 985 COPD patients in the IPPB trial 111 | IP 250 µg via air nebuliser | 15% | Per cent change from baseline | ||
| 150 patients with airway obstruction 113 | SB 200 µg or TB 500 µg via MDI | 15% (0.33 L) | 10% (0.16 L) | 95% CI for absolute change | |
| 78 patients with COPD/asthma 101 | SB 200 µg via MDI | 14% (0.51 L) | 15% (0.25 L) | 95% CL per cent change of baseline |
FVC: forced vital capacity; FEV1: forced expiratory volume in one second; MEF25–75%: mean flow between 25% and 75% of FVC; MEF50%: flow at 50% of FVC; IP: isoproterenol; MDI: metered dose inhaler; TB: terbutaline; % pred: % predicted; SB: salbutamol; CL: confidence limits; PFT:pulmonary function tests; CI: confidence interval; COPD: chronic obstructive pulmonary disease; IPPB: intermittent positive pressure breathing; Other variables as in table 6⇑.