Hepatitis C infection epidemiology in Mongolia: protocol of a systematic review and meta-analysis

BACKGROUND: Hepatitis C virus (HCV) morbidity appears to be high in Mongolia. Yet, the scale and nature of the infection burden is not well-understood. Our study’s objective is to systematically review and synthetize all available epidemiological data on HCV antibody (Ab) prevalence, ribonucleic acid (RNA) prevalence, incidence, risk factors to HCV exposure, and circulating HCV genotypes/subtypes among different at-risk populations. Additionally, we aim to estimate national population-level HCV-Ab prevalence and the number of HCV chronically infected individuals in the population of Mongolia. METHODS: Our systematic review will be reported based on the items outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2009) statement. All reports with primary data collected from surveillance or observational studies on Mongolian populations will be eligible for inclusion if the study sample size is greater than 25. Included reports need to present studies that use biological assay for HCV-Ab ascertainment. We will consider three primary outcomes of interest: HCV-Ab incidence, HCV-Ab prevalence, and HCV genotypes/subtypes among different at-risk populations. In addition, two secondary outcomes of interests will be also collected: HCV RNA prevalence, and unadjusted and/or adjusted statistically significant risk factors for HCV exposure (p value ≤0.05). In order to identify relevant reports, we will search PubMed, Embase, and Index Medicus for the Southeast Asian region. Additionally, we will search Mongolian scientific and medical journals not indexed in PubMed or Embase and the archives of Mongolian local conferences. Lastly, the literature search will be supplemented by checking references of the included reports and identified reviews. We will use broad search criteria with no language or time restrictions. Meta-analyses will estimate pooled HCV-Ab prevalence (by at-risk population, sex, age group, and period), and pooled RNA prevalence among HCV-Ab positive individuals in the general population. Age-adjustment of estimates will be conducted. DISCUSSION: The proposed systematic review and meta-analysis will produce a comprehensive synthesis of HCV epidemiology in Mongolia. The study will provide empirical evidence to inform health policy decision-making, resource allocation, and planning and implementation of relevant public health interventions. SYSTEMATIC REVIEW REGISTRATION: We have not registered with PROSPERO ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13643-017-0558-8) contains supplementary material, which is available to authorized users.