Prevalence and associated risk indicators of early childhood caries in Nigeria: a systematic review and meta-analysis

Early childhood caries (ECC) is a disease of global public health significance and a source of concern, especially in resource-poor countries like Nigeria. This study aims to determine the prevalence and associated risk indicators for ECC in Nigeria. This systematic review protocol for this systematic review was registered on PROSPERO (CRD420250654057). A systematic search of PubMed, Web of Science, African Journals Online, Scopus, ProQuest, and Directory of Open Access Journals was conducted from inception to April 1, 2025, for studies reporting the prevalence of ECC and its risk indicators in children in Nigeria aged 0–71 months. Grey literature was sought from the Nigeria and West Africa Postgraduate Medical Colleges. Eligible studies included peer-reviewed articles, conference proceedings, government and international organization reports, and unpublished studies. Quality was assessed using the Joanna Briggs Institute checklist. A random effect model was used to calculate the pooled prevalence, and sensitivity and subgroup analysis were performed to explore heterogeneity. Thirty-one studies published between 2006 and 2025 were included in the systematic review, and 27 in the meta-analysis. The pooled prevalence of ECC was 22% (95% CI: 17–26%; I²=98%), decreasing to 19% (95% CI: 15–23) after the sensitivity analysis. Subgroup analysis revealed no significant difference in the prevalence over time (p = 0.060) or by sex (females slightly higher, p = 0.720). Regional prevalence was highest in the Northeast and Southwest (p < 0.001), children from high-income groups had the highest ECC prevalence (p = 0.030), and prevalence increased significantly with age (p < 0.001). Approximately one in every five children in Nigeria has ECC, indicating a substantial burden. These findings underscore the need for sustained preventive strategies and have significant implications for oral health policy and practice in Nigeria. Registered on PROSPERO on 24th February 2025 with registration number: CRD420250654057.