Type 2 diabetes mellitus increases liver transplant-free mortality in patients with cirrhosis: A systematic review and meta-analysis

Table 2 Newcastle-Ottawa Scale score

Ref.	Year	Type of study	Selection	Comparability	Outcome	Score
Bianchi et al[14]	1994	Retrospective cohort	4	1	3	8
Quintana et al[5]	2011	Prospective cohort	4	2	2	8
Ahn et al[4]	2020	Retrospective cohort	4	0	2	6
Wlazlo et al[6]	2013	Retrospective cohort	3	0	3	6
Holstein et al[10]	2002	Prospective cohort	4	2	2	8
Elkrief et al[7]	2014	Retrospective cohort	3	0	3	6
Liu et al[8]	2016	Retrospective cohort	3	0	3	6
Veldt et al[13]	2008	Prospective cohort	3	0	3	6
Yin et al[11]	2019	Prospective cohort	3	1	3	7
Wang et al[12]	2020	Retrospective cohort	3	1	2	6
Nishida et al[15]	2006	Prospective cohort	4	2	2	8
Ioannou et al[19]	2006	Retrospective cohort	3	2	3	8
N’kontchou et al[20]	2006	Retrospective cohort	3	0	3	6
Labenz et al[21]	2020	Prospective cohort	3	1	3	7
Torisu et al[16]	2007	Retrospective cohort	3	0	3	6
Braia et al[18]	2016	Prospective cohort	4	0	2	6
Yang et al[17]	2007	Retrospective cohort	4	0	3	7