Early treatment efficacy of S-adenosylmethionine in patients with intrahepatic cholestasis: A systematic review

Table 2 Risk-of-bias assessments for included randomized studies

Study	Risk of bias (domains)
	Inadequate sequence generation	Inadequate allocation concealment	Inadequate blinding	Inadequate handling of incomplete outcome data	Selective reporting of outcomes	Other bias
Frezza et al[33], 1990	Low	Unclear	Low	Low	Low	Low
Manzillo et al[38], 1992	Low	Unclear	Low	Low	Low	Low
Qin et al[37], 2000	Low	Unclear	Unclear	Low	Low	High

Risk of bias within each domain was judged as low, unclear, or high, using the Cochrane risk-of-bias tool for randomized studies[28].