Background: There are still some unsolved questions regarding population-based screening program for H. pylori infection to prevent gastric cancer, such as how to perform the optimal screening strategies.~Objective: A prospective, randomized trial will be conducted to compare the acceptability, compliance (/adherence), and accuracy of C13 UBT and HpSA in a population-based H. pylori screening and gastric cancer prevention program.~Methods：Open labeled, randomized controlled trial The investigators will recruit 10,000 adults with age of ≥20 years who have not received H. pylori screening or treatment. Eligible patients will be randomly 1:1:1:1 allocated to (A) The carbon-13 urea breath test (C13 UBT), (B) H. pylori stool antigen test (Vstrip® HpSA), (C) Both C13 UBT and HpSA, (D) Two-stage screening method (serology screening only, and then C13 UBT for confirmation if serology test is positive).~Outcome analysis:~Detection rate of H. pylori infection~To compare the compliance(/adherence) of screening tests for H. pylori infection in the two randomized groups.~To assess the diagnostic accuracy of these tests.~To verify the compliance(/adherence) and feasibility of this two-stage screening method~Long-term Outcomes: To assess the risk reduction of gastric cancer
There are still some unsolved questions regarding population-based screening program for H. pylori infection to prevent gastric cancer, such as how to perform the optimal screening strategies. A prospective, randomized trial will be conducted to compare the acceptability, compliance (/adherence), and accuracy of diagnostic tests in a population-based H. pylori screening and gastric cancer prevention program. The investigators will recruit 10,000 adults with age of ≥20 years who have not received H. pylori screening or treatment. Eligible patients will be randomly 1:1:1:1 allocated to four groups with different combination tests.