How Electronic Cigarette Affects the Vascular System

Table 4

Risk of bias assessment of 6 animal studies using SYRCLE’s RoB.

Criteria	El-Mahdy et al. [21]	Espinoza-Derout et al. [22]	Kuntic et al. [23]	Li et al. [24]	Olfert et al. [25]	Szostak et al. [26]
Random group allocation (selection bias)	Unclear	No	No	No	Unclear	Unclear
Groups similar at baseline (selection bias)	Yes	Unclear	Unclear	Unclear	Yes	Yes
Blinded group allocation (selection bias)	No	No	No	No	No	No
Random housing (performance bias)	No	No	No	No	No	No
Blinded intervention (performance bias)	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Random outcome assessment (detection bias)	Unclear	Unclear	Unclear	Unclear	Unclear	Unclear
Blinded outcome assessment (detection bias)	No	No	No	No	No	No
Reporting of drop-outs (attrition bias)	Yes	Yes	Yes	Yes	Yes	Yes
Selective outcome reporting	Yes	Yes	Yes	Yes	Yes	Yes
Other biases	Yes	Yes	Yes	Yes	Yes	Unclear

Notes: In the SYRCLE’s RoB, ‘Yes’ indicates low risk of bias; No indicates high risk of bias; ‘Unclear’ indicates unclear risk of bias.