title: Does the NBME Surgery Shelf exam constitute a "double jeopardy" of USMLE Step 1 performance?
abstract: BACKGROUND
  Scores from the NBME Subject Examination in Surgery (Surgery Shelf) positively correlate with United States Medical Licensing Examination Step 1 (Step 1). Based on this relationship, the authors evaluated the predictive value of Step 1 on the Surgery Shelf.
  
  
  METHODS
  Surgery Shelf standard scores were substituted for Step 1 standard scores for 395 students in 2012-2014 at one medical school. Linear regression was used to determine how well Step 1 scores predicted Surgery Shelf scores. Percent match between original (with Shelf) and modified (with Step 1) clerkship grades were computed.
  
  
  RESULTS
  Step 1 scores significantly predicted Surgery Shelf scores, R2= 0.42, P < 0.001. For every point increase in Step 1, a Surgery Shelf score increased by 0.30 points. Seventy-seven percent of original grades matched the modified grades.
  
  
  CONCLUSIONS
  Replacing Surgery Shelf scores with Step 1 scores did not have an effect on the majority of final clerkship grades. This observation raises concern over use of Surgery Shelf scores as a measure of knowledge obtained during the Surgery clerkship.
authors.affiliation: Virginia Commonwealth University School of Medicine, 1201 East Marshall Street, Richmond, VA, 23298, USA.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Ryan
authors.affiliation: University of Utah School of Medicine, 30 N 1900 E, Salt Lake City, UT, 84132, USA.
authors.forename: Jorie M
authors.initials: JM
authors.lastname: Colbert-Getz
authors.affiliation: Virginia Commonwealth University School of Medicine, 1201 East Marshall Street, Richmond, VA, 23298, USA.
authors.forename: Salem N
authors.initials: SN
authors.lastname: Glenn
authors.affiliation: Virginia Commonwealth University School of Medicine, 1201 East Marshall Street, Richmond, VA, 23298, USA.
authors.forename: Joel D
authors.initials: JD
authors.lastname: Browning
authors.affiliation: Virginia Commonwealth University School of Medicine, 1201 East Marshall Street, Richmond, VA, 23298, USA. Electronic address: Rahul.anand@vcuhealth.org.
authors.forename: Rahul J
authors.initials: RJ
authors.lastname: Anand
mesh_terms: D002982:Clinical Clerkship; D004521:Educational Measurement; D013502:General Surgery / Q000193:education*; D006801:Humans; D008007:Licensure, Medical; D016014:Linear Models; D014481:United States
keywords: Surgery Shelf exam; Surgery clerkship; USMLE Step 1 exam