title: An independent interobserver reliability and intraobserver reproducibility evaluation of the new AOSpine Thoracolumbar Spine Injury Classification System.
abstract: METHODS
  Agreement study.
  
  
  OBJECTIVE
  To perform an independent interobserver and intraobserver agreement evaluation of the new AOSpine Thoracolumbar Spine Injury Classification System.
  
  
  BACKGROUND
  The new AOSpine Thoracolumbar Spine Injury Classification System was recently published. It showed substantial reliability and reproducibility among the surgeons who developed it; however, an independent evaluation has not been performed.
  
  
  METHODS
  Anteroposterior and lateral radiographs, and computed tomographic scans of 70 patients with acute traumatic thoracolumbar injuries were selected and classified using the morphological grading of the new AOSpine Thoracolumbar Spine Injury Classification System by 6 evaluators (3 spine surgeons and 3 orthopedic surgery residents). After a 6-week interval, the 70 cases were presented in a random sequence to the same evaluators for repeat evaluation. The Kappa coefficient (κ) was used to determine the interobserver and intraobserver agreement.
  
  
  RESULTS
  The interobserver reliability was substantial when considering the fracture type (A, B, or C), with a κ= 0.62 (0.57-0.66). The interobserver agreement when considering the subtypes was moderate; κ= 0.55 (0.52-0.57). The intraobserver reproducibility was also substantial, with 85.95% full intraobserver reproducibility considering the fracture type, with κ= 0.77 (0.72-0.83), and was also substantial when considering subtypes with 75.71% full agreement and κ= 0.71 (0.67-0.76). No significant differences were observed between spine surgeons and orthopedic residents in the overall interobserver reliability and intraobserver reproducibility, or in the inter- and intraobserver agreement of specific A, B, or C types of injuries.
  
  
  CONCLUSIONS
  This classification allows adequate agreement among different observers and by the same observer on separate occasions. Future prospective studies should evaluate whether this classification improves clinical decision making.
authors.affiliation: *Department of Orthopaedic Surgery, School of Medicine, Pontificia Universidad Catolica de Chile, Santiago, Chile; and †Department of Orthopaedic Surgery, Clinica Alemana de Santiago, Chile.
authors.forename: Julio
authors.initials: J
authors.lastname: Urrutia
authors.forename: Tomas
authors.initials: T
authors.lastname: Zamora
authors.forename: Ratko
authors.initials: R
authors.lastname: Yurac
authors.forename: Mauricio
authors.initials: M
authors.lastname: Campos
authors.forename: Joaquin
authors.initials: J
authors.lastname: Palma
authors.forename: Sebastian
authors.initials: S
authors.lastname: Mobarec
authors.forename: Carlos
authors.initials: C
authors.lastname: Prada
mesh_terms: D002983:Clinical Competence; D005257:Fellowships and Scholarships; D006801:Humans; D007396:Internship and Residency; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries*; D015588:Observer Variation; D009985:Orthopedics; D011859:Radiography; D015203:Reproducibility of Results; D016103:Spinal Fractures / Q000145:classification* / Q000000981:diagnostic imaging; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging / Q000293:injuries*