Comparison 2. Melatonin versus placebo: safety.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 number of adverse event reports per person	1	151	Mean Difference (IV, Fixed, 95% CI)	0.20 [‐0.72, 1.12]
1.1 melatonin (immediate‐release)	1	73	Mean Difference (IV, Fixed, 95% CI)	‐0.40 [‐1.62, 0.82]
1.2 melatonin slow‐release	1	78	Mean Difference (IV, Fixed, 95% CI)	1.0 [‐0.41, 2.41]
2 adverse event severity	1	151	Mean Difference (IV, Fixed, 95% CI)	0.10 [‐0.06, 0.26]
2.1 melatonin (immediate‐release)	1	73	Mean Difference (IV, Fixed, 95% CI)	0.10 [‐0.11, 0.31]
2.2 melatonin slow‐release	1	78	Mean Difference (IV, Fixed, 95% CI)	0.10 [‐0.13, 0.33]
3 reporting at least one adverse event	1	151	Risk Ratio (M‐H, Fixed, 95% CI)	1.07 [0.86, 1.33]