Efficacy of sorafenib combined with transarterial chemoembolization in the treatment of advanced hepatocellular carcinoma: A meta-analysis

Table 2 The quality assessment according to Newcastle-Ottawa Scale of each cohort study

Ref.	Selection			Comparability		Outcome			Total score
	Representativeness of the exposed cohort	Selection of the non-exposed cohort	Ascertainment of exposure	Demonstration that outcome of interest was not present at start of study	Comparability of cohorts on the basis of the design or analysis	Assessment of outcome	Was follow-up long enough	Adequacy of follow up of cohorts
Zhao et al[20]		1	1	1	2	1	1	1	8
Ikuta et al[19]	1	1	1	1	2	1	1	1	9
Bai et al[24]	1	1	1	1	2	1	1	1	9
Muhammad et al[25]	1	1	1	1	1	1	1	1	8
Qu et al[21]	1	1	1	1	1	1	1	1	8