Table 3 The methodological quality of the trials

Selection

Method used to generate randomisation sequence?

'Patients were allocated with minimisation to intervention using the programme MINIM v1.3'

'Randomisation was performed by the clinical pharmacist who randomised an odd number dice roll to placebo and an even number dice roll to drug'

'Randomisation was performed in blocks of six by computer generated allocation'

'A randomisation schedule generated by the patient allocation for clinical trials (PACT) program'

Method used to generate allocation concealment?

'Inhalers were given an alphanumeric code to conceal allocation'

Inadequate

Unclear

Unclear

Performance

Double-blinding?

'Study nurses and regular clinicians were blind to allocation throughout the study'

'The subject and pulmonary physician were blinded to the treatment regimen. Placebo and drug MDI canisters were identical, and the placebo mist was flavoured to make the treatments indistinguishable'

'This study was a randomised, double-blind parallel-group single centre study...'

'the study medication was packed in identical inhaler devices to ensure both the patient and investigator were unaware of the allocated treatment'

Attrition

Loss of patients accounted for?

Steroid

Placebo

Unclear

Steroid

Placebo

Steroid

Placebo

Number randomised

128

132

Number randomised

123

121

Number randomised

189

184

Number analysed

128

132

Number analysed

122(1 died)

120(1 died)

Number analysed

unclear

unclear

Detection

Outcome assessor blind

Unclear

Unclear

Unclear

Unclear

Reporting

Any evidence of reporting bias?

No

No

No

No