Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Change in croup score
Systematic review	287 children 5 RCTs in this analysis	Mean between-group change in croup score from baseline (assessed using Westley Croup Score [see table 1 ]) 6 hours with nebulised budesonide (166 children) with placebo (121 children) Absolute results not reported	WMD –1.37 95% CI –2.06 to –0.68 P = 0.00011 Heterogeneity: I2 = 55%, P = 0.07 See Further information on studies	Effect size not calculated	nebulised budesonide
Systematic review	127 children 2 RCTs in this analysis	Mean between-group change in croup score from baseline (assessed using Westley Croup Score [see table 1]) 12 hours with nebulised budesonide (71 children) with placebo (56 children) Absolute results not reported	WMD –1.34 95% CI –2.03 to –0.65 P = 0.00015	Effect size not calculated	nebulised budesonide
Systematic review	67 children Data from 1 RCT	Mean between-group change in croup score from baseline (assessed using Westley Croup Score [see table 1]) 24 hours –4.14 with nebulised budesonide (35 children) –2.11 with placebo (32 children)	WMD –2.03 95% CI –3.30 to –0.76 P = 0.0017	Effect size not calculated	nebulised budesonide