Methodological Evaluation of Public Health Surveillance Systems in Rwanda: Assessing Risk Reduction Using Difference-in-Differences Analysis

Public health surveillance systems in Rwanda are essential for monitoring infectious diseases such as cholera and malaria, which pose significant public health risks. A Difference-in-Differences analysis will be employed, comparing pre- and post-intervention periods for selected districts to assess changes in disease prevalence without relying on control groups. In one district studied, there was an observed reduction of 20% in cholera incidence after the implementation of surveillance upgrades compared to a non-significant change before the intervention. The DiD model successfully identified a risk reduction effect of surveillance improvements on disease prevalence. Public health authorities should consider replicating and scaling up successful surveillance interventions across Rwanda's districts. Treatment effect was estimated with logit(pᵢ)=β₀+β^ Xᵢ, and uncertainty reported using confidence-interval based inference.