2.1 | Data sources and search strategy
We systematically searched PubMed, Embase, Web of Science, and the Cochrane Library for studies that assessed the diagnostic accuracy of RAC for H. pylori infection. Our medical subject heading terms (for PubMed), EMTREE terms (for Embase), and search text (for others) were ”(”Kyoto classification of gastritis” OR ”endoscopic findings” OR (endoscopic features) OR ”regular arrangement of collecting venules” OR RAC) AND (”Helicobacter pylori” OR H. pylori).” The detailed search strategy is shown in Supplementary Table 1 . We searched the databases between inception and Oct 29, 2020. The reference list of each primary study identified was also searched.