Bass 2010.

Methods	Randomised clinical trial
Participants	Country: USA, Canada, Russia Period of recruitment: 2005–2008 Number randomised: 299 Postrandomisation dropouts: 0 (0%) Revised sample size: 299 Mean age (years): 56 Females: 117 (39.1%) Presence of other features of decompensation (hepatorenal syndrome, hepatic encephalopathy, or variceal bleeding): 299 (100%) Ascites with low protein: not stated Primary prophylaxis: not stated Alcohol‐related cirrhosis: not stated Viral‐related cirrhosis: not stated Autoimmune disease‐related cirrhosis (e.g. PSC, PBC, AIH): not stated Other causes for cirrhosis: not stated Treated for ascites in addition to antibiotics (e.g. albumin or diuretics): not stated Inclusion criteria: ≥ 2 episodes of overt hepatic encephalopathy Exclusion criteria: gastrointestinal bleeding recent portosystemic shunt or transjugular intrahepatic portosystemic shunt comorbidities such as chronic renal insufficiency or respiratory insufficiency electrolyte insufficiency
Interventions	Participants randomly assigned to 2 groups. Group 1: rifaximin (n = 140) Further details: rifaximin 550 mg BD for 6 months or until recurrence of hepatorenal syndrome Group 2: no active intervention (n = 159) Further details: placebo for 6 months
Outcomes	Outcomes reported: all‐cause mortality; number of serious adverse events per participant; proportion of people with any adverse events; number of any adverse events per participant; number of other decompensation events. Follow‐up (months): 6
Notes	Trial name/trial registry number: NCT00298038 Attempted to contact authors in November 2018, but received no replies
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Comment: information not available
Allocation concealment (selection bias)	Unclear risk	Comment: information not available
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Quote: "Double‐blind placebo‐controlled trial."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Double‐blind placebo‐controlled trial."
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: no postrandomisation dropouts.
Selective reporting (reporting bias)	Low risk	Comment: protocol not available, but authors reported mortality and adverse events adequately.
Other bias	Low risk	Comment: no other bias noted