District hospitals in Tanzania face challenges in implementing effective healthcare systems. The study utilised DiD to measure changes in health indices pre- and post-improvement interventions at district hospitals across Tanzania. A significant reduction of 20% in patient mortality rates was observed after the implementation of system improvements, with a confidence interval around the mean difference of -20.5% ± 4.3%. The DiD model effectively quantified risk reduction in district hospitals, highlighting areas for further improvement. Continued monitoring and refinement of healthcare systems are recommended to sustain these gains and address remaining disparities. District Hospitals, Tanzania, Difference-in-Differences (DiD), Risk Reduction Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.