| Methods |
Study Design: Parallel RCT
Randomisation: randomised in balanced blocks of 4 at each treatment centre.
Concealment of Allocation: opaque consecutive numbered envelopes, identical placebo
Double Blinding: Yes
Withdrawals / dropouts: described
Adverse events: described
Statistical analysis: intention to treat
Jadad Score: 5 |
| Participants |
Study site: multicentre
No eligible: 1114
No randomised: 852 (213/210/214/215)
No completed: 694
Sex: Males 416 (49%); Females 436 (51%)
Age (mean, range): Intervention 1: 42 (18‐70); Intervention 2: 41 (18‐68); Intervention 3: 44 (18‐70); Intervention 4: 42 (17‐70)
Diagnostic criteria for asthma: doctor diagnosis and objective lung function
Inclusion criteria: asthma > 6 months, ICS maintenance >3 months, FEV1 > 50% predicted, > 15% reversibility.
Exclusion criteria: 3 or more courses OCS or hospitalisation in past 6 months, ICS doses > 2000mcg BDP, > 1600mcg BUD(pMDI), > 800mcg FP, or > 800mcg BUD(DPI).
Baseline severity of asthma: FEV1% (mean): 75.8/75.7/75.4/76.3; Morning PEF: 397/399/381/394; Evening PEF: 402/402/387/402 |
| Interventions |
Run in phase: BUD 800mcg twice daily for 4 weeks then randomised if compliant (75‐125% ) and stable asthma.
1: BUD 100mcg + placebo twice daily (N/A)
2: BUD 100mcg + Formoterol 12mcg twice daily
3: BUD 400mcg + placebo twice daily
4: BUD 400mcg + Formoterol 12mcg twice daily (N/A)
Delivery device: DPI
Duration of treatment: 12 months
Other: |
| Outcomes |
Withdrawal due to severe exacerbations, overall withdrawals, exacerbations, FEV1 % predicted, morning PEF, episode free days, symptoms, rescue medications (no of puffs), hospitalisations, QOL. SDs were calculated based on an ITT analysis |
| Notes |
Comparison 1: Constant dose ICS (interventions 2&3) |
| Risk of bias |
| Bias |
Authors' judgement |
Support for judgement |
| Adequate sequence generation? |
Low risk |
Computer generated randomisation scheme |
| Allocation concealment? |
Low risk |
Opaque consecutive numbered envelopes |
| Blinding?
All outcomes |
Low risk |
'All medications were inhaled by means of a multidose Turbuhaler.' |
