Data sources: The Latin American and Caribbean Health Sciences (LILACS), LIVIVO, PubMed/Medline, Science Direct, Web of Science, Google Scholar, Open Gray and ProQuest database.
Study selection: Observational studies conducted in adults aged over 18 where oral potentially malignant disorders (OPMDs) had clinical diagnoses histologically confirmed were included.
Data extraction and synthesis: Study selection and data abstraction were undertaken by two reviewers independently. The Joanna Briggs Institute checklist of prevalence data was used to assess risk of bias. The prevalence of OMPDs expressed as a percentage was the main outcome. Random effects meta-analysis and sensitivity analysis were conducted.
Results: Twenty two studies were included, seven from South America or the Caribbean, five from Asia, five from Europe and two each from North America and the Middle East. Three studies were considered to have a low risk of bias, twelve a moderate risk and seven a high risk of bias. The overall pooled prevalence of OPMD in this study was 4.47% (95% CI; 2.43-7.08). OPMDs were more common in males 59.99% (95% CI; 41.27-77.30%). Prevalence was highest in Asian populations 10.54% (95% CI; 4.60-18.55%).
Conclusions: The overall prevalence of OPMD worldwide was 4.47%, and males were more frequently affected by these disorders. The prevalence of OPMD differs between populations; therefore, further population-based studies may contribute to the better understanding of these differences.