{ "background": "The effectiveness of community health centre (CHC) systems in sub-Saharan Africa hinges on their adoption by local communities. While numerous CHC models have been implemented, robust methodological frameworks for evaluating their real-world adoption rates are lacking, particularly in rural settings.", "purpose and objectives": "This protocol details a methodological assessment of a randomised field trial designed to measure the adoption rate of a new CHC system in Rwanda. The primary objective is to estimate the causal effect of system introduction on household utilisation. Secondary objectives include identifying demographic and socio-economic moderators of adoption.", "methodology": "A cluster-randomised controlled trial will be conducted across 60 villages. Villages will be randomly assigned to receive the new CHC system (intervention) or continue with standard care (control). The primary outcome is the proportion of households with at least one recorded CHC visit over a 12-month period. Adoption will be modelled using a hierarchical logistic regression: $\\logit(p{ij}) = \\beta0 + \\beta1 Tj + \\gamma X{ij} + uj$, where $p{ij}$ is the probability of adoption for household $i$ in village $j$, $Tj$ is the treatment assignment, $X{ij}$ a vector of covariates, and $uj$ a village-level random effect. Inference will be based on cluster-robust standard errors.", "findings": "As a protocol, no empirical findings are presented. The anticipated primary result is a point estimate for the risk difference in adoption rates between intervention and control clusters, reported with its 95% confidence interval. A key methodological output will be the validated measurement framework for adoption.", "conclusion": "This protocol provides a novel, rigorous methodological blueprint for evaluating the uptake of community-based health interventions. The trial design is intended to yield an unbiased estimate of adoption, addressing a critical gap in implementation science for African food and health systems.", "recommendations": "Researchers employing field trials for health system evaluation