Comparison 1. Corticosteroids vs no corticosteroid use.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Incidence of coronary artery abnormalities	7	907	Odds Ratio (M‐H, Fixed, 95% CI)	0.29 [0.18, 0.46]
2 Incidence of serious adverse effects attributable to steroid use	6	737	Odds Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
3 Mortality (all‐cause)	7	915	Odds Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
4 Duration of clinical symptoms: fever, rash	2	210	Mean Difference (IV, Random, 95% CI)	‐1.65 [‐3.31, 0.00]
5 Time for laboratory parameters to normalise: CRP, ESR	1	178	Mean Difference (IV, Fixed, 95% CI)	‐2.80 [‐4.38, ‐1.22]
6 Length of hospital stay	1	39	Mean Difference (IV, Fixed, 95% CI)	‐1.41 [‐2.36, ‐0.46]