Community health centers (CHCs) in Tanzania play a crucial role in delivering primary healthcare services to underserved populations. A mixed-methods approach was employed, including quantitative data collection through standardised health surveys and qualitative insights from focus group discussions. The study utilised a difference-in-differences (DiD) regression model to analyse clinical outcomes. CHCs in this region demonstrated an improvement in vaccination coverage by 15% over the two-year period, with significant confidence intervals indicating robust statistical significance. The quasi-experimental design proved effective in measuring CHC clinical performance and highlights the need for further policy interventions to address identified gaps. Enhancements to health infrastructure and training programmes are recommended to sustain these positive outcomes. Community Health Centers, Clinical Outcomes Assessment, Quasi-Experimental Design Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.