Gauvreau 1996.

Methods	Setting: Canada, hospital outpatient clinic Randomisation: yes, computer‐generated randomisation schedule Allocation concealment: yes, randomisation sequence concealed in envelopes. Design: crossover, 3 week washout Intervention period: 1 week Masking: double blind Excluded: not stated Withdrawals: stated Baseline data: no data according to treatment sequence Jadad score=4
Participants	9 adults: 4M 5F Age range: 19‐24 years Inclusion criteria: Mild asthma FEV1 (% predicted) > 70 Non‐smokers Exclusion criteria: Respiratory tract infection or exacerbation of asthma in previous 6 weeks
Interventions	BUD: 400 mcg/d Placebo Delivery device: DPI
Outcomes	Methacholine BHR (PC20 FEV1) pre and 24 hr post allergen challenge Largest % fall in FEV1 within 2 hrs of inhaled allergen (house dust mite, rag weed or cat): early allergen response Largest % fall in FEV1 3‐7 hrs after inhaled allergen: late allergen response Sputum eosinophil count Blood eosinophil count
Notes	Reply from author confirming use of allocation concealment, delivery device used. Author also provided log transformed data for pre‐allergen challenge methacholine bronchial responsiveness (log 10 PC20 FEV1). Only the pre‐allergen challenge data for methacholine bronchial challenge is included in the meta‐analysis.
Risk of bias
Bias	Authors' judgement	Support for judgement
Allocation concealment?	Low risk	A ‐ Adequate