Table 2.

Summary of Studies of Chemopreventive Effect of Metformin Against Hepatocellular Carcinoma

Study	Design	Location	Subjects	Metformin	HCC Cases	Results
Oliveria et al. (2008)25	Population‐based cohort	United States	191,223	NR	39	AOR: 0.7 (0.3–1.6)
Ruiter et al. (2012)26	Population‐based cohort	Netherlands	85,289	61.8%	31	OR: 0.7 (0.5–0.9)
Chen et al. (2013)11	Population‐based case–control	Taiwan	47,820	NR	22,047	AOR: 0.8 (0.7–0.8)
Kawaguchi et al. (2010)27	Hospital‐based case–control	Japan	241	3.7%	138	AOR: 0.6 (0.2–2.2)
Hassan et al. (2010)28	Hospital‐based case–control	United States	255	47.1%	140	AOR: 0.3 (0.2–0.6)
Donadon et al. (2010)29	Hospital‐based case–control	Italy	549	23.5%	190	AOR: 0.2 (0.1–0.4)
Nkontchou et al. (2011)30	Hospital‐based cohort	France	100	26.0%	39	AOR: 0.2 (0.04–0.8)
RECORD (2010)31	RCT	International	4447	75.2%	4	AOR: 3.0 (0.2–55.3)

Abbreviations: NR, not reported; OR, odds ratio.