Database	Time span of search	Search strategy
The Cochrane Hepato‐Biliary Group Controlled Trials Register	The date when the search is performed.	(antibiotic* OR 'antibacterial agent*' OR aminoglycosid* OR imidazole* OR rifaximin* OR vancomycin* OR neomycin* OR paromomycin* OR metronidazole*) AND 'hepatic encephalopath*'
Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library	Latest issue.	#1 (antibiotic* OR antibacterial agent* OR aminoglycosid* OR imidazole* OR rifaximin* OR vancomycin* OR neomycin* OR paromomycin* OR metronidazole*) in All Fields in all products #2 MeSH descriptor Anti‐Bacterial Agents explode all trees in MeSH products #3 MeSH descriptor Aminoglycosides explode all trees in MeSH products #4 MeSH descriptor Imidazoles explode all trees in MeSH products #5 MeSH descriptor Vancomycin explode all trees in MeSH products #6 MeSH descriptor Metronidazole explode all trees in MeSH products #7 (#1 OR #2 OR #3 OR #4 OR #5 OR #6) #8 hepatic encephalopathy in All Fields in all products #9 MeSH descriptor Hepatic Encephalopathy explode all trees in MeSH products #10 (#8 OR #9) #11 (#7 AND #10)
MEDLINE (OVID)	1966 to the date the search is performed.	#1 Randomized controlled trial pt. #2 Controlled clinical trial.pt. #3 Randomized controlled trials/ #4 random allocation/ #5 double‐blind method/ #6 single‐blind method/ #7 clinical trial.pt. #8 exp clinical trials/ #9 (clin$ adj25 trial$).ti,ab,sh. #10 or/1‐9 #11 singl$ or doubl$ or tripl$ or trebl$).ti,ab,sh. #12 (blind$ or mask$).ti,ab,sh. #13 11 and 12 #14 placebos/ #15 placebo$.ti,ab,sh #16 random$.ti,ab,sh. #17 Research design/ #18 or/14‐17 #19 10 or 13 or 18 #20 animal/ not human/ #21 19 not 20 #22 Anti‐bacterial agents/ #23 exp aminoglycosides/ #24 Vancomycin/ #25 exp imidazoles/ #26 Rifaximin.mp. #27 or/22‐26 #28 Hepatic encephalopathy/ #29 21 and 27 and 28
EMBASE	1980 to the date the search is performed.	#1 Controlled study #2 Randomized Controlled trial/ #3 double blind procedure/ #4 single blind procedure/ #5 crossover procedure/ #6 drug comparision/ #7 placebo/ #8 random$.ti,ab,hw,tn,mf. #9 latin square.ti,ab,hw,tn,mf. #10 crossover.ti,ab,hw,tn,mf. #11 cross‐over.ti,ab,hw,tn,mf. #12 placebo$.ti,ab,hw,tn,mf. #13 ((doubl$ or singl$ or tripl$ or trebl$) adj5 (blind$ or mask$)).ti,ab,hw,tn,mf. #14 (comparative adj5 trial$).ti,ab,hw,tn,mf. #15 (clinical adj5 trial$).ti,ab,hw,tn,mf. #16 or/ 1‐15 #17 nonhuman/ #18 animal/ not (human/and animal/) #19 or/17‐18 #20 16 not 19 #21 Anti‐bacterial agents/ #22 exp aminoglycosides/ #23 exp Vancomycin/ #24 exp imidazoles/ #25 exp Rifaximin/ #26 or/21‐25 #27 exp Hepatic encephalopathy/ #28 26 AND 27 #29 20 AND 28
Science Citation Index Expanded (SCI Expanded) (http://portal.isiknowledge.com/portal.cgi?DestApp=WOS&Func=Frame)	1945 to the date the search is performed.	#1 TS=(antibiotic* OR 'antibacterial agent*' OR aminoglycosid* OR imidazole* OR rifaximin* OR vancomycin* OR neomycin* OR paromomycin* OR metronidazole*) #2 TS=(hepatic encephalopath*) #3 #2 AND #1 #4 TS=(random* OR blind* OR placebo* OR meta‐analysis) #5 #4 AND #3
LILACS	1980 to the date the search is performed.	(antibiot$ or aminog$ or rifaxim$ or imidaz$ or metron$ or neom$ or paramom$ or vancom$) AND (hepatic encephalopathy or encefalopatia hepatica)