Digestive Disease Center;
Soonchunhyang University Hospital;
Seoul 04401;
South Korea Department of Pathology;
Soonchunhyang University Hospital;
Seoul 04401;
South Korea;
Department of Pathology;
Soonchunhyang University Hospital;
Seoul 04401;
South Korea;
Department of Medical Biostatistics;
Soonchunhyang University Hospital;
Seoul 04401;
South Korea;
Endoscopy; Magnifying narrow-band imaging; Helicobacter pylori; Gastric atrophy; Intestinal metaplasia; Pepsinogen;