Helicobacter pylori prevalence in the Southwest of China: A protocol for systematic review

OBJECTIVES: This epidemiological research will be aimed to evaluate the longitudinal changes of Helicobacter pylori prevalence in Southwest China during recent period through a systematic review and analysis. METHODS: The database PubMed and China National Knowledge Infrastructure will be searched. The cross-sectional studies or cohort studies on either massive or hospital-based health checkup population will be potentially eligible. The study population was originated from one of the southwestern major cities, Chengdu (Sichuan), Chongqing, Kunming (Yunnan), Guiyang (Guizhou), or Lhasa (Tibet). Two reviewers will independently select studies, extract data, and assess the quality of studies. The prevalence of H pylori infection will be estimated. In the individual city, the longitudinal comparisons will be conducted to evaluate the trends referring to the earliest cross-sectional baseline. The risk ratio and its 95% confidence interval will be estimated. Subgroup analyses will be performed in sex-specific and age-specific subsets. Trend analysis for proportions (p for trend) will be estimated in the longitudinal evaluation. If applicable, the longitudinal clearance rate (%) will be estimated. ETHICS AND DISSEMINATION: The ethical approval is not required due to the nature of literature-based research. The results will be disseminated through meetings and a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42019120764