['Increasing studies have investigated the relationship between the status of H.\xa0pylori vacA antibody and risks of peptic ulcer disease (PUD) and gastric cancer (GC). However, the results were controversial. The aim of this meta-analysis is to clarify whether serum vacA antibody is associated with risks of PUD and GC.', 'Databases including PubMed, Embase, Web of knowledge, Wanfang, Chinese National Knowledge Infrastructure (CNKI), OVID, Karger and Scopus were systematically searched for potentially eligible literature. Odds ratios (OR) and their 95% confidence interval (CI) were adopted to assess the strength of association.', 'Serum VacA antibody was associated with increased risk of PUD compared with gastritis/functional dyspepsia (FD) (OR\xa0=\xa01.96, 95%CI\xa0=\xa01.56-2.46, P\xa0<\xa00.001). Serum VacA antibody was significantly associated with increased risk of gastric ulcer (GU) and duodenal ulcer (DU) compared with gastritis/FD (GU: OR\xa0=\xa01.64, 95%CI\xa0=\xa01.02-2.62, P\xa0=\xa00.042; DU: OR\xa0=\xa02.06, 95%CI\xa0=\xa01.50-2.84, P\xa0<\xa00.001, respectively). Significant increased risk of GC was found in serum VacA antibody positive subjects compared with serum VacA antibody negative individuals (OR\xa0=\xa02.78, 95%CI\xa0=\xa01.98-3.89, P\xa0<\xa00.001). There was no significant publication bias in all of the comparisons.'] Is serum VacA antibody associated with risks of peptic ulcer and gastric cancer : A meta-analysis?