{ "background": "Rural primary healthcare delivery in sub-Saharan Africa faces systemic challenges, including workforce shortages and fragmented service models, which impact clinical outcomes. Evidence on the comparative effectiveness of different organisational structures within routine clinic settings remains limited.", "purpose and objectives": "This study aimed to evaluate the impact of two distinct primary care delivery models—a decentralised, nurse-led model versus a standard, doctor-supervised model—on a composite measure of chronic disease control among adult patients in a rural setting.", "methodology": "We conducted a pragmatic, parallel-group, randomised field trial. Twenty-four rural clinics were matched and randomly allocated to implement one of the two delivery models. Adult patients with hypertension and/or type 2 diabetes were enrolled. The primary outcome was the proportion achieving controlled blood pressure and HbA1c at 12 months. Analysis used a mixed-effects logistic regression model: $logit(P(Y{ij}=1)) = \\beta0 + \\beta1 X{ij} + uj + e{ij}$, where $u_j$ represents clinic random effects, with robust standard errors.", "findings": "Patients in clinics assigned to the nurse-led model (n=1,247) were significantly more likely to achieve the composite outcome of disease control compared to those in doctor-supervised clinics (n=1,198) (adjusted odds ratio 1.48, 95% CI 1.12 to 1.96). This corresponds to an absolute increase of 8.7 percentage points in the proportion of patients with controlled disease.", "conclusion": "A reorganised, decentralised nurse-led primary care model improved clinical outcomes for chronic disease management in a resource-constrained rural setting compared to a traditional doctor-centric approach.", "recommendations": "Health policy should consider task-shifting and organisational redesign to empower nurse-led teams within supported decentralised structures. Further research should investigate the cost-effectiveness and long-term sustainability of this model.", "key words": "primary health care, task shifting,