Grangie 1998.

Methods	Randomised clinical trial
Participants	Country: France Period of recruitment: 1991–1993 Number randomised: 107 Postrandomisation dropouts: 0 (0%) Revised sample size: 107 Mean age (years): 55 Females: 38 (35.5%) Presence of other features of decompensation (hepatorenal syndrome, hepatic encephalopathy, or variceal bleeding): not stated Ascites with low protein: not stated Primary prophylaxis: 107 (100%) Alcohol‐related cirrhosis: 93 (86.9%) Viral‐related cirrhosis: 10 (9.3%) Autoimmune disease‐related cirrhosis (e.g. PSC, PBC, AIH): not stated Other causes for cirrhosis: 4 (3.7%) Treated for ascites in addition to antibiotics (e.g. albumin or diuretics): not stated Exclusion criteria: active gastrointestinal bleeding hepatocellular carcinoma or other life‐threatening disease
Interventions	Participants randomly assigned to 2 groups. Group 1: norfloxacin (n = 53) Further details: norfloxacin 400 mg daily (duration not stated, but probably to end of follow‐up) Group 2: no active intervention (n = 54) Further details: placebo
Outcomes	Outcomes reported: all‐cause mortality; number of any adverse events per participant; proportion with spontaneous bacterial peritonitis (as per definition) Follow‐up (months): 6
Notes	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."
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "Double‐blind, placebo‐controlled."
Incomplete outcome data (attrition bias) All outcomes	Low risk	Comment: no postrandomisation dropouts
Selective reporting (reporting bias)	High risk	Comment: protocol not available, and authors did not report the outcomes assessed adequately.
Other bias	Low risk	Comment: no other bias noted