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. Initially, we planned to recruit 10,000 adults aged ≥20 years who had not previously undergone H. pylori screening or treatment. Eligible participants were to be randomly allocated in a 1:1:1:1 ratio to one of four groups, each receiving a different combination of diagnostic tests. However, a preliminary analysis led to a recalculation of the required sample size. Following the approval of an Institutional Review Board (IRB) amendment, enrollment was discontinued for Group B (HpSA method) and Group D (Two-stage screening method). The final number of participants enrolled in Group B and Group D was 852 and 851, respectively. Groups A (UBT method) and Group C (standard method) will continue to enroll participants through an additional 1:1 randomization until each group reaches a total of 1,350 participants.