Methodological Evaluation and Multilevel Regression Analysis of Public Health Surveillance System Reliability in Nigeria

Public health surveillance systems are critical for disease control, yet their operational reliability in resource-limited settings is often inadequately quantified. In Nigeria, systemic challenges such as infrastructure deficits and inconsistent reporting protocols necessitate a rigorous methodological evaluation. This study aimed to methodologically evaluate the reliability of the national integrated disease surveillance and response system and to identify the key facility- and state-level determinants of reporting consistency. We conducted a secondary analysis of national surveillance performance data. Reliability was operationalised as the consistency of weekly reporting over a continuous period. A three-level hierarchical logistic regression model was fitted: logit (P (Y₈₉₊=1) ) = ₀ + u₉₊ + vₖ, where Y₈₉₊ is the timely report from facility i in district j and state k, with random effects u₉₊ and vₖ. Robust standard errors were used for inference. Facility-level factors, notably access to dedicated internet connectivity (OR=2. 34, 95% CI: 1. 87–2. 93), were stronger predictors of reliability than state-level funding allocations. The intra-class correlation indicated that 31% of the variance in reliability was attributable to state-level differences. The reliability of surveillance is predominantly influenced by operational infrastructure at the point of reporting, rather than broader administrative or financial inputs. Investment should prioritise sustainable infrastructure, particularly digital connectivity, at primary healthcare facilities. Training programmes must be reinforced with continuous technical support to maintain reporting fidelity. health surveillance, system reliability, multilevel modelling, health systems research, Nigeria This study provides a novel application of multilevel regression to quantify the hierarchical determinants of surveillance system reliability, offering a replicable methodological framework for similar evaluations in other regions.