Private-Sector Contribution to Tuberculosis Case Notification in Nigeria: A Systematic Review and Meta-Analysis

Tuberculosis (TB) remains a leading cause of infectious disease mortality worldwide, and Nigeria contributes disproportionately to the global burden.More than half of Nigerians with TB symptoms first seek care from private providers; the private sector's contribution to national TB case notification has not been formally distilled.This review estimated the contribution following PRISMA 2020 and a registered protocol.Six databases and grey literature sources were searched from January 2000 to December 2023.Two reviewers screened records and assessed risk of bias using the Newcastle-Ottawa Scale, ROBINS-I, and JBI checklist.Proportions were pooled using the DerSimonian-Laird random-effects estimator.Heterogeneity was assessed with I², τ², and Cochran's Q and explored through subgroup and meta-regression analyses; bias was evaluated using Egger's test.Of 1,673 unique records screened, 28 studies met the eligibility criteria, and 18 studies (47,342 notifications) were included in the primary meta-analysis.The pooled privatesector contribution was 16.8% (95% CI 15.6-18.0;I² = 90.7%;τ² = 0.028), exceeding the WHO benchmark of 15%.Results withstood sensitivity checks.The study-level share did not change significantly over 2009-2023 (meta-regression p = 0.678).Contributions were higher in private hospitals (19.2%) and laboratories (21.0%) than in mixed portfolios (16.2%) or medicine-vendor channels (14.5%).No publication bias was detected (Egger p = 0.944).Engaged private providers account for one in six notified TB cases in Nigeria; sustaining and expanding this contribution requires an institutionalised public-private mix, predictable domestic financing, and the integration of TB notification into health insurance benefit packages.