Urban primary care networks (PNCs) in Ghana have been implemented to improve access to healthcare services and address health inequalities. A comprehensive search strategy was employed to identify relevant studies. Studies were assessed based on their adherence to rigorous research methodologies and the use of difference-in-differences (DiD) models. One study demonstrated that implementing DiD models could significantly improve clinical outcomes in urban PNCs, with an estimated effect size of +20% in favour of the intervention group. The findings suggest that DiD models offer a robust method for evaluating the impact of primary care interventions on patient outcomes. Further research should explore these findings within diverse urban settings and evaluate potential challenges to implementation. Primary Care Networks, Difference-in-Differences, Clinical Outcomes, Urban Healthcare, Ghana Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.