title: Radiographic fracture assessments: which ones can we reliably make?
abstract: OBJECTIVE
  To identify the fracture characteristics that can be reliably assessed by analysis of plain radiographs of tibial plateau fractures.
  
  
  METHODS
  Radiographic review study.
  
  
  METHODS
  Five orthopaedic traumatologists served as observers.
  
  
  METHODS
  Observers made assessments based on the radiographs of fifty-six tibial plateau fractures. Precise definitions of the assessments to be made were agreed on by all observers. The tested assessments included raters' abilities to identify and locate fracture lines, identify the presence of fracture displacement and comminution, make quantitative measurements of displacement, and characterize qualitative features of fractures. For thirty-eight of the fractures that had a computed tomography (CT) scan available, assessments were repeated using both radiographs and CT scans.
  
  
  METHODS
  To characterize interobserver reliability, percentage agreement and kappa statistics were calculated for categorical variables, and intraclass correlation coefficients (ICC) were calculated for noncategorical variables.
  
  
  RESULTS
  Reliability of the assessments varied widely. Determining the location of fracture lines had the greatest reliability, whereas the subjective assessments of fracture stability and energy showed the poorest reliability. Although the ICCs for quantitative measurements approached acceptable levels, the tolerance limits were extremely wide. The addition of a CT scan improved the reliability of most assessments, but not to a statistically significant degree.
  
  
  CONCLUSIONS
  Many basic radiographic interpretations relied on in making treatment decisions are made variably by observers. Using experienced raters and precise definitions of fracture assessments does not guarantee a high level of agreement. Discrete assessments have higher interrater agreements than do more qualitative assessments. Quantitative measures have wide tolerance limits and, therefore, probably cannot be used reproducibly to classify fractures or make treatment decisions. We conclude the reliability of fracture classification is limited by raters' abilities to agree on basic radiographic assessments.
authors.affiliation: University of Iowa Hospitals and Clinics, Iowa City, USA.
authors.forename: J
authors.initials: J
authors.lastname: Martin
authors.forename: J L
authors.initials: JL
authors.lastname: Marsh
authors.forename: J V
authors.initials: JV
authors.lastname: Nepola
authors.forename: D R
authors.initials: DR
authors.lastname: Dirschl
authors.forename: S
authors.initials: S
authors.lastname: Hurwitz
authors.forename: T A
authors.initials: TA
authors.lastname: DeCoster
mesh_terms: D006801:Humans; D015601:Injury Severity Score; D015588:Observer Variation; D009985:Orthopedics; D011859:Radiography / Q000592:standards; D012307:Risk Factors; D013978:Tibial Fractures / Q000145:classification / Q000150:complications / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000592:standards; D014194:Traumatology