title: Identification of significant difficulty of selective deep cannulation by a simple predictive model: an endoscopic scale for teaching ERCP.
abstract: BACKGROUND
  Endoscopic retrograde cholangiopancreatography (ERCP) is an advanced endoscopic procedure associated with a risk of serious complications. This cohort study was designed to assess the accuracy of an endoscopic method aimed at discriminating procedures eligible to teach ERCP: patients with and without significant difficulty of selective deep cannulation (DSDC).
  
  
  METHODS
  Clinically relevant variables were analyzed in a cohort of 400 consecutive patients (estimation group = 250 patients; validation group = 150 patients) who underwent an ERCP procedure.
  
  
  RESULTS
  Multivariate analysis identified fixated duodenum, inflamed duodenum, soft major papilla, previous biliary surgery, and papilla with ectopion as independent predictors of DSDC. We constructed a model and a score system combining these five variables. The area under the ROC curve was 0.81 for the estimation group and 0.80 for the validation group. Using the best cutoff score (> 1.63), absence of significant DSDC could be excluded with high accuracy (negative predictive value = 89.2%) in 111 (44.4%) of 250 patients. Similarly, it could be excluded with the same certainty in 77 (51.3%) of the 150 patients in the validation group.
  
  
  CONCLUSIONS
  A combination of easily accessible variables accurately predicts the absence of significant DSDC in half the patients who underwent the ERCP procedure. This score system discriminates procedures eligible to teach ERCP.
authors: Endoscopy Unit, Department of Gastroenterology, Hospital Universitari Germans Trias i Pujol, Badalona, Barcelona, Spain.
authors: Jaume
authors: J
authors: Boix
authors: Vicente
authors: V
authors: Lorenzo-Zúñiga
authors: Vicente
authors: V
authors: Moreno de Vega
authors: Eduard
authors: E
authors: Cabré
authors: Fidel Ernesto
authors: FE
authors: Añaños
authors: Eugeni
authors: E
authors: Domènech
authors: Miquel Angel
authors: MA
authors: Gassull
mesh_terms: D000368:Aged; D002404:Catheterization / Q000379:methods*; D002760:Cholangiopancreatography, Endoscopic Retrograde / Q000379:methods*; D015331:Cohort Studies; D004724:Endoscopy / Q000193:education*; D005260:Female; D006801:Humans; D008297:Male; D017145:Models, Educational; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013663:Teaching / Q000379:methods*