BACKGROUND AND PURPOSE - A high rate of postprocedure complications in the Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis (SAMMPRIS) trial has raised concerns whether such results are representative of intracranial stent placement in actual routine practice. METHODS - Using the Nationwide Inpatient Sample from 2008 to 2010, patients with cerebral ischemic events treated with intracranial stent as part of a clinical trial or outside the trial were identified. The composite end point (postoperative stroke, cardiac complications, and mortality) was reported. RESULTS - Of the 3447 patients who underwent intracranial stent placement, 223 patients (6.5%) were enrolled in a clinical trial. The rate of composite end point was higher in patients treated outside clinical trials compared with those treated within clinical trials (14.2% versus 4.5%; P=0.1). The proportion of patients discharged to home was higher in those treated in clinical trials (76.8% versus 49.6%; P=0.001). CONCLUSIONS - Intracranial stent placement procedures outside a clinical trial have higher rates of postoperative stroke, cardiac complication, and mortality.