. 2020 Mar 9;14(6):792–807. doi: 10.5009/gnl19163

Table 3.

Methodological Quality of the Case-Control Study Included in the Final Analysis of Hepatocellular Carcinoma Incidence Based on the Newcastle-Ottawa Scale

Case-control study	Selection				Comparability	Outcome		Score

	Is the case definition adequate?	Representativeness of the cases	Selection of controls	Definition of controls	Comparability of cases and controls on the basis of the design or analysis	Ascertainment of exposure	Same method of ascertainment for cases and controls	Total (0–9)
Chen (1996)²⁸	☆	☆	☆	☆	☆☆	☆	☆	8
Ohishi (2008)²⁹	☆	☆	☆	☆	☆☆	☆	☆	8
Koh (2011)³⁰	☆	☆	☆	☆	☆☆	☆	☆	8
Trichopoulos (2011)³¹	-	☆	☆	☆	☆☆	☆	☆	7
Yuan (2004)³²	☆	☆	☆	☆	☆☆	☆	-	7
Loftfield (2016)³³	☆	-	☆	☆	☆☆	☆	☆	7
Yi (2018)³⁴	☆	☆	☆	☆	☆☆	☆	☆	8