Comparison 1. Antibiotics versus placebo/usual care.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Symptom score	2		Mean Difference (Fixed, 95% CI)	‐0.34 [‐0.60, ‐0.08]
1.1 Adults	2		Mean Difference (Fixed, 95% CI)	‐0.34 [‐0.60, ‐0.08]
1.2 Children	0		Mean Difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
2 All adverse events	3	506	Odds Ratio (M‐H, Fixed, 95% CI)	0.99 [0.69, 1.43]
2.1 Adults	2	462	Odds Ratio (M‐H, Fixed, 95% CI)	1.00 [0.69, 1.45]
2.2 Children	1	44	Odds Ratio (M‐H, Fixed, 95% CI)	0.78 [0.12, 5.18]
3 Serious adverse events	3	502	Risk Difference (M‐H, Fixed, 95% CI)	0.00 [‐0.03, 0.03]
3.1 Adults	2	462	Risk Difference (M‐H, Fixed, 95% CI)	0.00 [‐0.03, 0.03]
3.2 Children	1	40	Risk Difference (M‐H, Fixed, 95% CI)	0.0 [‐0.09, 0.09]
4 Length of hospital stay (days)	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
4.1 Adults	0		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
4.2 Children	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
5 PEF (GIV)	2		Mean Difference (Fixed, 95% CI)	23.42 [5.23, 41.60]
5.1 Adults	2		Mean Difference (Fixed, 95% CI)	23.42 [5.23, 41.60]
5.2 Children	0		Mean Difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
6 PEF	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
6.1 Adults	0		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
6.2 Children	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]