Methodological Inconsistencies in Nigerian HPV Systematic Reviews: A Meta- Epidemiological Analysis for Evidence-Based Policy

Abstract Background: Reliable estimates of human papillomavirus (HPV) prevalence are essential for informing vaccine policy, screening strategies, and resource allocation in high-burden settings like Nigeria. However, systematic reviews of HPV prevalence among Nigerian women have produced methodologically inconsistent and geographically contradictory results, limiting their utility for health economic and policy decision-making. Objective: This meta-epidemiological analysis critically evaluates systematic reviews published between 2020 and 2024, comparing methodological quality, diagnostic approaches, geographic coverage, HIV stratification, and genotype reporting. Methods: Systematic reviews were assessed using AMSTAR-2, and key epidemiological and methodological variables were extracted. Comparisons focused on pooled prevalence estimates, confidence intervals, heterogeneity metrics, and regional representation. Particular attention was paid to HIV co-infection stratification and genotype-specific prevalence. Results: Pooled HPV prevalence estimates ranged from 20.7–42%, with confidence interval widths varying more than tenfold across reviews. Geographic findings were inconsistent, with different regions identified as having the highest prevalence and contradictory estimates for the same zones (e.g., North West: 73% vs. 6.8%). Genotype distributions showed major inconsistencies, especially for high-risk types not covered by current vaccines. HIV-positive populations were either excluded, aggregated without stratification, or inadequately analyzed. AMSTAR-2 ratings ranged from high to critically low. Conclusion: Substantial methodological heterogeneity undermines the reliability of current HPV prevalence data for informing cost-effectiveness analyses, vaccine selection, and national cervical cancer prevention planning. This meta-epidemiological analysis critically evaluates the existing literature and is a roadmap for developing standardized surveillance protocols. It aims to create a more reliable evidence base to inform equitable, value-driven public health decisions.