The number of individuals needed to scan to prevent one extra stroke through referral for endarterectomy is 143 for claudicants, 250 for those with aortic aneurysmal disease and 333 for those with contralateral symptomatic carotid stenosis.
The cost per stroke saved with surgery is approximately 拢76,000, through a policy of testing claudicants for asymptomatic carotid atherosclerosis, then offering carotid endarterectomy. Through implementing large scale testing of claudicants aged 60 years in England and Wales, 0.2% of the total number of strokes per year would be saved at a cost of 拢17 million. The main cost driver is the amount of unnecessary surgery performed (number needed to treat=20).