['Despite the current Centers for Medicare and Medicaid Services coverage criteria for carotid artery stenting (CAS), consensus regarding its appropriateness in patients with carotid artery stenosis has not been reached. This is one of the first population-based studies to use a dedicated administrative convention for the endovascular procedure to address whether there is a cohort of patients in whom CAS is more beneficial than carotid endarterectomy (CEA).', 'We analyzed in-hospital mortality, postoperative stroke, and combined postoperative stoke/mortality in 47,752 CAS or CEA hospitalizations, matched by propensity score, in discharge data sets obtained from the states of New York and California for the years 2005 to 2007. Other outcomes included postoperative complications, length of stay, and volume-outcome relationships.', 'For symptomatic patients undergoing CAS, rates were significantly higher for in-hospital mortality (3.7% vs 1.3%) and combined stroke/mortality (8.3% vs 4.6%) compared with CEA. For asymptomatic patients, there was no statistical difference between mortality (0.6% vs 0.4%), stroke (2.0% vs 1.8%), or combined stroke/mortality (2.4% vs 1.9%) across the endovascular and open procedures, respectively. Postoperative respiratory and urinary complications as well as cranial neuropathy were more common after CEA, whereas postoperative complications, including device malfunction and hypotension, were more frequent after CAS. We did not find a volume-outcome relationship for CEA, but one did exist for CAS.'] Are outcomes of carotid stenting compared with endarterectomy equivalent in asymptomatic patients and inferior in symptomatic patients?