Clinical evaluation of prophylactic abdominal aortic balloon occlusion in patients with placenta accreta: a systematic review and meta-analysis

Table 1 Appraisal of methodological quality (Newcastle-Ottawa Scale)

Reference	Case-cohort representative	Selection of non-exposed control	Ascertainment of exposure	Outcome negative at start	Comparability by design	Comparability by analysis	Outcome assessment	Duration of follow-up	Adequacy of follow-up	Score
Panici et al., 2012 [15]	√	√	√	√	√	×	√	√	√	8
Qiu et al., 2015 [16]	√	√	√	√	√	×	√	√	√	8
Cui et al., 2016 [12]	√	√	√	√	√	×	√	√	√	8
Chen et al.,2016 [11]	√	√	√	√	×	×	√	√	√	7
Wu et al., 2016 [19]	√	√	√	√	×	√	√	√	√	8
Duan et al., 2016 [13]	√	√	√	√	√	√	√	√	√	9
Sun et al., 2018 [17]	√	√	√	√	√	×	√	√	√	8
Xie et al., 2017 [20]	√	√	√	√	√	×	√	√	√	8
Gong et al.,, 2017 [14]	√	√	√	√	√	×	√	√	√	8
Wang et al., 2017 [18]	√	√	√	√	√	×	√	√	√	8
Wei et al., 2018 [21]	√	√	√	√	×	×	√	√	√	7