Comparison 1. IM vitamin K vs. placebo or nothing.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 HDN/ VKDB	1	3338	Risk Ratio (M‐H, Fixed, 95% CI)	0.73 [0.56, 0.96]
1.1 At 1‐7 days	1	3338	Risk Ratio (M‐H, Fixed, 95% CI)	0.73 [0.56, 0.96]
2 Bleeding after circumcision	1	470	Risk Ratio (M‐H, Fixed, 95% CI)	0.18 [0.08, 0.42]
3 PIVKA II present	2		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
3.1 At 1‐7 days	2	58	Risk Ratio (M‐H, Fixed, 95% CI)	0.43 [0.26, 0.71]
3.2 At 1 month	1	16	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
4 Prothrombin index (% of normal)	1	50	Mean Difference (IV, Fixed, 95% CI)	14.40 [7.47, 21.33]
4.1 At 1‐7 days	1	50	Mean Difference (IV, Fixed, 95% CI)	14.40 [7.47, 21.33]