{ "background": "Community health centres are critical nodes in Nigeria's primary healthcare system, yet their operational resilience and capacity for risk reduction are inadequately quantified. Existing evaluations often lack methodological rigour, particularly in employing longitudinal data to model systemic vulnerabilities and health outcomes over time.", "purpose and objectives": "This systematic review aims to critically appraise methodological approaches used in evaluating these centres, with a specific focus on the application of panel-data econometric models for estimating risk reduction in service delivery and health outcomes.", "methodology": "A systematic search of multiple electronic databases was conducted following PRISMA guidelines. Studies were screened and selected based on pre-defined eligibility criteria focusing on methodological design and quantitative analysis. The quality and applicability of panel-data estimation techniques, such as the model $Y{it} = \\alpha + \\beta X{it} + \\mui + \\epsilon{it}$, were critically evaluated, with particular attention to the handling of unobserved heterogeneity and the use of robust standard errors.", "findings": "The review identified a predominant theme: studies employing fixed-effects models to control for time-invariant centre characteristics consistently produced more reliable estimates of intervention impacts. A key concrete finding is that panel models accounting for cluster-level effects showed that improved supply chain logistics were associated with a reduction in stock-out risk, with coefficient estimates indicating a 15-25% decrease, though confidence intervals were often wide due to small sample sizes.", "conclusion": "Panel-data methods are underutilised but offer a superior framework for causal inference and risk measurement in this context compared to cross-sectional designs. Their rigorous application can significantly enhance the evidence base for health systems strengthening.", "recommendations": "Future research should prioritise the collection of longitudinal data and the adoption of difference-in-differences or synthetic control methods to strengthen causal claims. Capacity building in advanced econometric techniques for health systems researchers is urgently needed.", "key words": "health systems research, panel data, econometric evaluation, primary healthcare, health services research, Nigeria",