Stroke Warning Information and Faster Treatment (SWIFT): Cost-Effectiveness of a Stroke Preparedness Intervention

Background: Less than 25% of stroke patients arrive to an emergency department within the 3-hour treatment window. Objective: We evaluated the cost-effectiveness of a stroke preparedness behavioral intervention study (Stroke Warning Information and Faster Treatment [SWIFT]), a stroke intervention demonstrating capacity to decrease race-ethnic disparities in ED arrival times. Methods: Using the literature and SWIFT outcomes for 2 interventions, enhanced educational (EE) materials, and interactive intervention (II), we assess the cost-effectiveness of SWIFT in 2 ways: (1) Markov model, and (2) cost-to-outcome ratio. The Markov model primary outcome was the cost per quality-adjusted life-year (QALY) gained using the cost-effectiveness threshold of $100 000/QALY. The primary cost-to-outcome endpoint was cost per additional patient with ED arrival <3 hours, stroke knowledge, and preparedness capacity. We assessed the ICER of II and EE versus standard care (SC) from a health sector and societal perspective using 2015 USD, a time horizon of 5 years, and a discount rate of 3%. Results: The cost-effectiveness of the II and EE programs was, respectively, $227.35 and $74.63 per additional arrival <3 hours, $440.72 and $334.09 per additional person with stroke knowledge proficiency, and $655.70 and $811.77 per additional person with preparedness capacity. Using a societal perspective, the ICER for EE versus SC was $84 643 per QALY gained and the ICER for II versus EE was $59 058 per QALY gained. Incorporating fixed costs, EE and II would need to administered to 507 and 1693 or more patients, respectively, to achieve an ICER of $100 000/QALY. Conclusion: II was a cost-effective strategy compared with both EE and SC. Nevertheless, high initial fixed costs associated with II may limit its cost-effectiveness in settings with smaller patient populations.