Fifoot 2007.

Methods	Randomised double‐blind trial
Participants	Study period: July 2004 to October 2005 Setting: emergency department of Mater Childrens' Hospital, Brisbane, Australia Inclusion criteria: children aged 6 months to 6 years presenting to the emergency department with croup (Westley croup score ≥ 2) with parents available for telephone follow‐up 1 week following enrolment Exclusion criteria: chronic respiratory disease (excluding asthma); severe croup (Westley croup score > 7); known allergy or relative contraindication to steroids (varicella or exposure to varicella within the past 3 weeks, history of tuberculosis, diabetes, or hypertension, known immunodeficiency); treatment with steroids in the preceding week or with nebulised adrenaline en route or immediately on arrival in the emergency department Baseline demographics (N = 99): proportion male: treatment 1: 79%; treatment 2: 65%; treatment 3: 80% mean (SD) age in years: treatment 1: 1.76 (1.52); treatment 2: 1.53 (1.31); treatment 3: 1.74 (1.61) mean (SD) Westley croup score: treatment 1: 3.15 (0.89); treatment 2: 2.71 (0.84); treatment 3: 2.81 (0.87)
Interventions	Treatment 1 (N = 34): single 1 mg/kg dose of oral prednisolone Treatment 2 (N = 34): single 0.15 mg/kg dose of oral dexamethasone Treatment 3 (N = 31): single 0.60 mg/kg dose of oral dexamethasone Children who did not tolerate oral therapy after 2 attempts received nebulised budesonide.
Outcomes	Change in Westley croup score from baseline to 2 and 4 hours; re‐presentations with croup; use of epinephrine and use of supplemental glucocorticoids
Notes	Funding source: no external funding
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "Subjects were randomized (using a computer‐generated sequence)"
Allocation concealment (selection bias)	Unclear risk	Comment: insufficient information provided to judge
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "Recruiting staff and study investigators were blinded to treatment assignments. MCH pharmacists prepared each steroid agent as a solution, such that each child would receive an identical volume of preparation... flavoured to standardize taste and palatability"
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Recruiting staff and study investigators were blinded to treatment assignments. MCH pharmacists prepared each steroid agent as a solution, such that each child would receive an identical volume of preparation... flavoured to standardize taste and palatability"
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Comment: 13% (N = 13) loss to follow‐up. Losses balanced between groups. Did not use intention‐to‐treat analysis for the telephone follow‐up outcomes
Selective reporting (reporting bias)	Low risk	Comment: no deviations from protocol detected.
Other bias	Low risk	Comment: no other sources of bias identified.
Overall risk of bias All outcomes	Unclear risk	Comment: at least 1 domain judged as unclear risk, and no domains judged as high risk.