Abstract
Emergency care systems in sub-Saharan Africa face significant challenges, yet robust quantitative evaluations of their impact on clinical outcomes are scarce. Existing literature often lacks rigorous causal identification strategies. This study aimed to quantify the causal effect of a systematic reorganisation of hospital-based emergency units on patient mortality, using a quasi-experimental design. We employed a difference-in-differences model, $Y{it} = \beta0 + \beta1 (\text{Treat}i \times \text{Post}t) + \gammai + \deltat + \epsilon{it}$, where $Y_{it}$ is the mortality rate for hospital $i$ in period $t$. The analysis used patient-level administrative data from a national cohort. Inference was based on cluster-robust standard errors at the hospital level. The intervention was associated with a statistically significant reduction in all-cause 30-day mortality of 4.2 percentage points (95% CI: 2.1 to 6.3). This represents a relative decline of approximately 18% from the pre-intervention mean. The structured reorganisation of emergency care was causally linked to a substantial improvement in patient survival, demonstrating the potential for system-level interventions to enhance clinical outcomes. Health policy should prioritise investment in dedicated emergency care systems with standardised protocols. Future research should investigate the cost-effectiveness of such models and their applicability in lower-resource settings. Emergency medical services; health systems evaluation; difference-in-differences; mortality; South Africa; quasi-experimental design This study provides novel causal evidence on the effectiveness of an integrated emergency care model in a sub-Saharan African context, utilising a robust quasi-experimental methodology rarely applied in this setting.