Prevalence of periodontal disease among Indigenous and non-Indigenous populations: protocol for systematic review and meta-analysis.

Background: Indigenous populations globally experience worse oral health than their non-Indigenous counterpart. Globally, the occurrence of periodontal diseases such as gingivitis and chronic periodontitis is high among Indigenous people. This systematic review aims to quantify, at a global level, the prevalence of periodontal disease among Indigenous populations compared to non-Indigenous populations.

Methods: This review will only consider studies that have reported the prevalence (%) of periodontal disease among Indigenous and compared against non-Indigenous populations. Studies that have no comparative population or data only on one particular population or lack of data on periodontal clinical assessment will be excluded. An electronic search will be conducted using keywords and appropriate MeSH terms across several databases capturing both published and unpublished articles. The search will be conducted from the time of database inception to February 2021. After the initial search, duplicates will be removed, and the remaining titles and abstracts will be assessed for eligibility. The full text of eligible studies will be assessed by two independent reviewers who will also complete the critical appraisals and data extraction. Outcomes measures would be the mean prevalence (%) and standard deviation of periodontal disease among Indigenous and non-Indigenous populations. From the selected studies, we will conduct a random-effects meta-analysis using standardized mean difference as the effect measure. Forest plots will be used for the visualization of differences in the prevalence of periodontitis. A subgroup analysis will be conducted based on the definition of periodontitis, age, publication type, and geographical location. Heterogeneity among studies will be assessed by I and chi-square test. Egger's test and funnel plots will be used to assess publication bias.

Discussion: Our systematic review and meta-analysis will facilitate an increased understanding of the magnitude of periodontal disease inequalities that exist globally for Indigenous populations through pooled prevalence estimates. The findings will be helpful to design selective targeted preventive and interventional strategies for periodontal disease for reducing oral health inequalities at a global level.

Systematic Review Registration: PROSPERO CRD42020188531.