Urban primary care networks in Ghana are critical for improving access to healthcare services, particularly in underserved urban areas. However, the effectiveness of these systems needs rigorous evaluation. A longitudinal study design was employed to analyse data collected from urban primary care sites in Ghana over two years. The DID model was used to estimate the effect of network implementation on patient outcomes, accounting for temporal trends and other confounding factors. The DID analysis revealed a statistically significant improvement (p < 0.05) in outpatient clinic attendance rates among patients within the intervention group compared to controls over the study period. This study provides robust evidence supporting the positive impact of urban primary care networks on patient engagement and health outcomes, validating the use of DID for clinical outcome measurement. Future research should explore long-term effects and scalability of these interventions across different urban settings in Ghana and other similar contexts. Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.