Table 2.

Risk of bias assessment of included studies

Study	Q1	Q2	Q3*	Q4	Q5	Q6*	Q7*	Q8	Q9	Q10	Q11*	Q12	Q13*	Q14	Overall
Cohort studies according to NHLBI tool
Arabi, 2017	Yes	Yes	Yes	Yes	NR	Yes	Yes	No	Yes	NA	Yes	NR	CD	NA	High risk
Arabi, 2020	Yes	Yes	Yes	Yes	NR	Yes	Yes	Yes	Yes	NA	Yes	NR	CD	NA	High risk
Biglari, 2016	Yes	Yes	Yes	Yes	NR	Yes	Yes	Yes	Yes	NA	Yes	NR	CD	NA	High risk
Burke, 2019	Yes	Yes	Yes	Yes	NR	Yes	CD	Yes	Yes	NA	Yes	NR	CD	NA	High risk
Dobran, 2015	Yes	Yes	Yes	Yes	NR	Yes	Yes	No	Yes	NA	Yes	NR	Yes	NA	Some concern
Gaebler., 1999	Yes	Yes	Yes	Yes	NR	Yes	Yes	Yes	Yes	NA	Yes	NR	Yes	NA	Some concern
Grassner, 2016	Yes	Yes	Yes	Yes	NR	Yes	Yes	Yes	Yes	NA	Yes	NR	Yes	NA	Some concern
Jug, 2015	Yes	Yes	Yes	Yes	NR	Yes	Yes	Yes	Yes	NA	Yes	Yes	Yes	NA	Low risk
Lee, 2018	Yes	Yes	Yes	Yes	NR	Yes	Yes	No	Yes	NA	Yes	NR	Yes	NA	Some concern
Mattiassich, 2017	Yes	Yes	Yes	Yes	NR	Yes	Yes	Yes	Yes	NA	Yes	NR	Yes	NA	Some concern
McCarthy, 2011	Yes	Yes	Yes	Yes	NR	Yes	Yes	No	Yes	NA	Yes	NR	Yes	NA	Some concern
Nagata, 2016	Yes	Yes	Yes	Yes	NR	Yes	Yes	No	Yes	NA	Yes	NR	CD	NA	High risk
Nasi, 2019	Yes	Yes	Yes	Yes	NR	Yes	Yes	Yes	Yes	NA	Yes	NR	Yes	NA	Some concern
Tsuji, 2019	Yes	Yes	Yes	Yes	NR	Yes	CD	Yes	Yes	NA	Yes	NR	Yes	NA	High risk
Wutte, 2020	Yes	Yes	Yes	Yes	NR	Yes	Yes	Yes	Yes	NA	Yes	Yes	Yes	NA	Low risk
	D1	D2	D3	D4	D5
Clinical trial according Cochrane risk of bias assessment tool
Cengiz, 2008	Low	Low	Low	Low	Low	--	--	--	--	--	--	--	--	--	Low risk

Q: Signaling question; D: Domain; NR: Not reported; NA: Not applicable; CD: Cannot determine.

*, Any concern in these questions were considered as fetal error.