We examined the impact of primary stroke center (PSC) certification on emergency department (ED) use and outcomes within an integrated delivery system in which EDs underwent staggered certification.

A retrospective cohort study of 30 461 patients seen in 17 integrated delivery system EDs with a primary diagnosis of transient ischemic attack (TIA), intracranial hemorrhage, or ischemic stroke between 2005 and 2008 was conducted. We compared ED stroke patient visits across hospitals for (1) temporal trends and (2) pre- and post-PSC certification—using logistic and linear regression models to adjust for comorbidities, patient characteristics, and calendar time, to examine major outcomes (ED throughput time, hospital admission, radiographic imaging utilization and throughput, and mortality) across certification stages.

There were 15 687 precertification ED visits and 11 040 postcertification visits. Primary stroke center certification was associated with significant changes in care processes associated with PSC certification process, including (1) ED throughput for patients with intracranial hemorrhage (55 minutes faster), (2) increased utilization of cranial magnetic resonance imaging for patients with ischemic stroke (odds ratio, 1.88; 95% confidence interval, 1.36-2.60), and (3) decrease in time to radiographic imaging for most modalities, including cranial computed tomography done within 6 hours of ED arrival (TIA: 12 minutes faster, ischemic stroke: 11 minutes faster), magnetic resonance imaging for patients with ischemic stroke (197 minutes faster), and carotid Doppler sonography for TIA patients (138 minutes faster). There were no significant changes in survival.

Stroke center certification was associated with significant changes in ED admission and radiographic utilization patterns, without measurable improvements in survival.