Nonbismuth concomitant quadruple therapy for Helicobacter pylori eradication in Chinese regions: A meta-analysis of randomized controlled trials

Table 2 Assessment of methodological quality of included studies

Ref.	Region	Allocation generation	Allocation concealment	Blinding of patients and assessors	Data analysis	Loss to follow up	Selective reporting	Other bias
Ang et al[36] (2015)	Singapore	Sealed envelope	Adequate	Open-label	ITT/PP	10.0%	Low risk	Not all patients underwent antibiotic susceptibility testing
Hsu et al[33] (2014)	Taiwan	Compute generated	Adequate	Open-label	ITT/PP	0.3%	Low risk	Not all patients underwent antibiotic susceptibility testing
Huang et al[22] (2012)	Taiwan	Computer generated	Unclear	Open-label	ITT/PP	6.5%	Low risk	No patient underwent antibiotic susceptibility testing
Tai et al[34] (2015)	Taiwan	Computer generated	Adequate	Unclear	ITT/PP	8.0%	Low risk	Not all patients underwent antibiotic susceptibility testing
Wang et al[35] (2014)	China	Computer generated	Unclear	Unclear	ITT/PP	1.2%	Low risk	No patient underwent antibiotic susceptibility testing
Wu et al[20] (2010)	Taiwan	Computer generated	Unclear	Outcome assessor blinded	ITT/PP	0.4%	Low risk	Not all patients underwent antibiotic susceptibility testing

Risk of bias was assessed according to the method recommended by the Cochrane Collaboration. ITT: Intention-to-treat; PP: Per-protocol.