Kemp 1999 b.

Methods	DESIGN: multi‐centre, randomised, double‐blind, placebo‐controlled, parallel‐group study
Participants	SYMPTOMATIC PARTICIPANTS RANDOMLY ASSIGNED: N = 174 INTERVENTION: ICS (budesonide 250 μg/d): 91 CONTROL: ICS (budesonide 1000 μg/d): 93 WITHDRAWALS: reported AGE: mean (range) (months) INTERVENTION: ICS (budesonide 250 μg/d): 55.2 ± 25.5 (7‐107) CONTROL: ICS (budesonide 1000 μg/d): 56.0 ± 27.2 (6‐107) GENDER: male N (%) INTERVENTION: ICS (budesonide 250 μg/d): 63 (69.2) CONTROL: ICS (budesonide 1000 μg/d): 56 (60.2) ASTHMA SEVERITY: mild persistent asthma ASTHMA DURATION: mean (range) in months INTERVENTION: ICS (budesonide 250 μg/d): 35.4 ± 22.4 (5‐97) CONTROL: ICS (budesonide 1000 μg/d): 36.1 ± 24.4 (5‐107) MEAN (± SD) β2‐AGONIST USE (puffs/d): not reported DOSE OF ICS AT STUDY ENTRY AND AT RUN‐IN: not reported. Participants discontinued their chronic asthma medication at the end of the study ATOPY (% of participants): not reported ELIGIBILITY CRITERIA As above EXCLUSION CRITERIA As above
Interventions	PROTOCOL DURATION Run‐in = 2 weeks Intervention = 12 weeks DEVICE: Pari LC‐Jet Plus nebuliser (with mouthpiece or face mask) DOSE OF ICS INTERVENTION: budesonide 250 μg/d CONTROL: budesonide 1000 μg/d CRITERIA FOR WITHDRAWAL FROM STUDY: not reported
Outcomes	As above
Notes	As above
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Insufficient information on sequence generation
Allocation concealment (selection bias)	Unclear risk	Insufficient information
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Blinding of participants and key study personnel ensured
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Blinding of participants and key study personnel ensured
Incomplete outcome data (attrition bias) All outcomes	Low risk	No missing outcome data
Selective reporting (reporting bias)	Low risk	Study protocol not available but published reports include all expected outcomes, including those that were prespecified
Other bias	Low risk	Study apparently free of other sources of bias