A list of 12000 subjects from GCS participants will be prepared. Sampling will be done using a cluster randomization method. Each village will be considered as a cluster. Clusters will randomly be allocated into two groups, the intervention group (group 1) and the control group (group 2). Capsule sponge examination will be performed for all subjects in intervention clusters. But, participants in control clusters will be enrolled without capsule sponge examination. Both intervention and control subjects will be offered endoscopy if they develop upper GI symptoms according to current clinical practice.