title: Picking the good apples: statistics versus good judgment in choosing stent operators for a multicenter clinical trial.
abstract: OBJECTIVE
  The Carotid Revascularization Endarterectomy Versus Stenting Trial was completed with a low stroke and death rate. A lead-in series of patients receiving carotid artery stenting was used to select the physician-operators for the study, where performance was evaluated by complication rates and by peer review of cases. Herein, we assess the potential contribution of statistical evaluation of complication rates.
  
  
  METHODS
  The ability to discriminate between stent operators who can successfully meet the published guideline of <3% combined rate of stroke and death is calculated under the binomial distribution, based on a small consecutive case series (n=24 patients).
  
  
  RESULTS
  A criterion of ≤2 stroke or death events among the 24 patients (<8% event rate) was required of operators. Setting such a high criterion, however, ensures an inability to exclude operators who cannot meet the criteria. In fact, if a good operator is defined as having a 2% event rate and a poor operator as a 6% event rate, even a series of 240 patients would (on average) still exclude 5.4% of the good operators and include 4.6% of the poor operators.
  
  
  CONCLUSIONS
  The low periprocedural event rates in the trial suggest success in separating skillful operators from less skillful. However, it seems unlikely that statistical assessment of event rates in the lead-in contributed to successful selection, but rather successful selection was more likely because of peer review of subjective and other factors including patient volume and technical approaches.
  
  
  BACKGROUND
  http://www.clinicaltrials.gov. Unique identifier: NCT00004732.
authors.affiliation: From the Departments of Biostatistics (G.H.) and Epidemiology (V.J.H.), University of Alabama at Birmingham, School of Public Health; Department of Neurology, Medical University of South Carolina, Charleston (J.H.V.); and Department of Neurology, Mayo Clinic Jacksonville, FL (J.F.M., T.G.B.).
authors.forename: George
authors.initials: G
authors.lastname: Howard
authors.affiliation: From the Departments of Biostatistics (G.H.) and Epidemiology (V.J.H.), University of Alabama at Birmingham, School of Public Health; Department of Neurology, Medical University of South Carolina, Charleston (J.H.V.); and Department of Neurology, Mayo Clinic Jacksonville, FL (J.F.M., T.G.B.).
authors.forename: Jenifer H
authors.initials: JH
authors.lastname: Voeks
authors.affiliation: From the Departments of Biostatistics (G.H.) and Epidemiology (V.J.H.), University of Alabama at Birmingham, School of Public Health; Department of Neurology, Medical University of South Carolina, Charleston (J.H.V.); and Department of Neurology, Mayo Clinic Jacksonville, FL (J.F.M., T.G.B.).
authors.forename: James F
authors.initials: JF
authors.lastname: Meschia
authors.affiliation: From the Departments of Biostatistics (G.H.) and Epidemiology (V.J.H.), University of Alabama at Birmingham, School of Public Health; Department of Neurology, Medical University of South Carolina, Charleston (J.H.V.); and Department of Neurology, Mayo Clinic Jacksonville, FL (J.F.M., T.G.B.).
authors.forename: Virginia J
authors.initials: VJ
authors.lastname: Howard
authors.affiliation: From the Departments of Biostatistics (G.H.) and Epidemiology (V.J.H.), University of Alabama at Birmingham, School of Public Health; Department of Neurology, Medical University of South Carolina, Charleston (J.H.V.); and Department of Neurology, Mayo Clinic Jacksonville, FL (J.F.M., T.G.B.). brott.thomas@mayo.edu.
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Brott
mesh_terms: D002548:Cerebral Revascularization / Q000592:standards / Q000706:statistics & numerical data; D002755:Choice Behavior; D002983:Clinical Competence / Q000592:standards* / Q000706:statistics & numerical data; D016894:Endarterectomy, Carotid / Q000592:standards* / Q000706:statistics & numerical data; D006801:Humans; D007600:Judgment; D010820:Physicians / Q000592:standards* / Q000706:statistics & numerical data; D011446:Prospective Studies; D015607:Stents / Q000592:standards* / Q000706:statistics & numerical data
keywords: clinical trial; quality control; stroke