Table 1

Characteristics of studies included in the review

Study referenceParticipantsIntervention
FEV1=forced expiratory volume in 1 second; VC=vital capacity.
Dullinger et al910 men with slowly progressive exertion, FEV1 <1.5 l with no documented history of asthma1 week treatment with metaproterenol, 1.3 mg from a metered dose canister or placebo six times a day and oral theophylline or placebo. Washout period details not reported
Guyatt et al527 men with FEV1 <70% predicted and FEV1/VC ratio <0.7. Less than 25% increase in FEV1 after salbutamol2 week treatment with inhaled salbutamol 200 μg four times a day and/or oral theophylline. For washout period the authors excluded first 3 days’ data from the analysis
Guyatt et al632 men with greater or less than 25% increase in FEV1 after salbutamol2 week treatment with inhaled salbutamol 200 μg four times a day and/or oral theophylline. Excluded first 3 days’ data
Guyatt et al732 men with greater or less than 25% increase in FEV1 after salbutamol2 week treatment with inhaled salbutamol 200 μg four times a day and/or oral theophylline. Excluded first 3 days’ data
Hansen et al1248 patients (24 men) with history of chronic bronchitis, FEV1 <1 litre, never treated with a nebuliser or oxygen at home5 mg terbutaline or placebo from a nebuliser twice daily for 2 weeks. Washout was 2 week run in period
Jaeschke et al824 patients (same who completed Guyatt et al7)2 week treatment with inhaled salbutamol 200 μg four times a day and/or oral theophylline. Excluded first 3 days’ data
Klock et al1015 patients (12 men) with ATS 1962 criteria for chronic bronchitis and FEV1 <65% predicted3 week period of 20 sprays (1 mg) of 1:100 atropine sulphate, 1:100 isoproterenol HCl, or placebo four times a day from a nebuliser. Washout period 2 weeks
Light et al1116 patients with FEV1 <2 l, FEV1/FVC ratio <50%8 week period of isoproterenol 250 mg or placebo from nebuliser four times a day. Washout period 2 weeks
Shah et al1612 patients with COPD (mean FEV1 0.6 l) and <15% reversibility on spirometry1 week treatment with 200 μg salbutamol 4-hourly or placebo from metered canister. Washout period 1 week
Silins et al138 men with severe airflow limitation due to COPD, previously on chronic treatment with inhaled β2 agonistFour 1-week periods, 2 with terbutaline 5 mg four times a day and 2 with placebo from nebuliser. Washout period 1 week
Tandon et al1437 men with a history of chronic bronchitis, FEV1 <65% predicted in the past 2 years6 week treatment with 4 puffs terbutaline (1 mg) four times a day and oral theophylline twice a day. Washout period 2 weeks
Taylor et al1725 patients (21 men) with chronic bronchitis and >10% improvement in FEV1 after salbutamolFour 3-week periods with 200 μg salbutamol or placebo four times a day from metered canisters and/or oral theophylline twice a day. Excluded first 3 days’ data
Wilson et al1510 patients (9 men) with severe chronic airway obstruction and marked dyspnoea not improved after high dose oral steroids2 week periods with 5 mg salbutamol or placebo four times a day from a nebuliser. Washout not discussed