Shapiro 1998 b.

Methods	DESIGN: randomised, double‐blind, placebo‐controlled, parallel‐group, multi‐centre study
Participants	SYMPTOMATIC PARTICIPANTS RANDOMLY ASSIGNED: N = 201 ANALYSED: N = 75 INTERVENTION: ICS (budesonide 100 μg/d): 102 CONTROL: ICS (budesonide 400 μg/d): 99 WITHDRAWALS: reported AGE: mean (range) years INTERVENTION: ICS (budesonide 100 μg/d): 11.8 (6‐18) CONTROL: ICS (budesonide 400 μg/d): 11.8 (6‐18) GENDER: male N (%) INTERVENTION: ICS (budesonide 100 μg/d): 76 (74.5) CONTROL: ICS (budesonide 400 μg/d): 85 (85.8) ASTHMA SEVERITY: moderate to severe persistent asthma ASTHMA DURATION: duration of ICS‐dependent asthma: mean (range) years INTERVENTION: ICS (budesonide 100 μg/d): 2.8 (0.5‐11) CONTROL: ICS (budesonide 400 μg/d): 2.4 (0.5‐13) MEAN (± SD) β2‐AGONIST USE (puffs/d): INTERVENTION: ICS (budesonide 100 μg/d): 2.8 CONTROL: ICS (budesonide 400 μg/d): 3.2 DOSE OF ICS AT STUDY ENTRY AND AT RUN‐IN: Participants discontinued their previous ICS at randomisation ATOPY (% of participants): not reported ELIGIBILITY CRITERIA As above EXCLUSION CRITERIA As above
Interventions	PROTOCOL DURATION Run‐in = 2 weeks Intervention = 12 weeks DEVICE: dry powder inhaler DOSE OF ICS INTERVENTION: budesonide 100 μg/d CONTROL: budesonide 400 μg/d CRITERIA FOR WITHDRAWAL FROM STUDY: 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