title: Classifying intertrochanteric fractures of the proximal femur: does experience matter?
abstract: OBJECTIVE
  This prospective study aimed to evaluate inter-observer agreement of the AO/OTA and Evans/Jensen classification systems with an emphasis on the effect of reviewer experience. In addition, the level of agreement in the determination of fracture stability across varying levels of experience was evaluated.
  
  
  METHODS
  A group of 12 reviewers (6 surgeons, 3 senior residents, 3 junior residents) independently assessed 56 radiographs of intertrochanteric hip fractures and classified them using the AO/OTA and Evans/Jensen systems. Reviewers further assessed the stability of the fracture patterns.
  
  
  RESULTS
  Overall, higher agreement was obtained for the AO/OTA classification than with the Evans/Jensen classification. However, neither classification system met acceptable thresholds for reliability. Surgeons were unable to reliability determine if fractures were stable or unstable. Increased experience improved AO/OTA classification reliability and assessment of stability but decreased agreement in the Evans/Jensen classification.
  
  
  CONCLUSIONS
  The AO/OTA classification should be used in favor of the Evans/Jensen classification whenever possible. Our findings suggest that surgeons' perceptions about stability vary to a significant extent thereby necessitating clear definitions of stability.
authors.affiliation: Division of Orthopaedic Surgery, McMaster University and the Clinical Research Group, Hamilton, Ontario, Canada.
authors.forename: Wayne
authors.initials: W
authors.lastname: Fung
authors.forename: Anders
authors.initials: A
authors.lastname: Jonsson
authors.forename: Volker
authors.initials: V
authors.lastname: Buhren
authors.forename: Mohit
authors.initials: M
authors.lastname: Bhandari
mesh_terms: D002983:Clinical Competence; D005270:Femur Head / Q000000981:diagnostic imaging / Q000293:injuries*; D006620:Hip Fractures / Q000145:classification* / Q000000981:diagnostic imaging; D006801:Humans; D007396:Internship and Residency; D015588:Observer Variation; D011446:Prospective Studies; D011859:Radiography