title: Low-field magnetic resonance imaging of the lumbar spine: reliability of qualitative evaluation of disc and muscle parameters.
abstract: OBJECTIVE
  To determine the intra- and interobserver reliability in grading disc and muscle parameters using low-field magnetic resonance imaging (MRI).
  
  
  METHODS
  MRI scans of 100 subjects representative of the general population were evaluated blindly by two radiologists. Criteria for grading lumbar discs were based on the spinal nomenclature of the Combined Task Force and the literature. Consensus in rating was achieved by evaluating 50 MRI examinations in tandem. The remaining 50 examinations were evaluated independently by the observers to determine interobserver agreement and re-evaluated by one of the observers to determine intra-observer agreement.
  
  
  RESULTS
  Intra- and interobserver agreement was substantial when grading changes in the lumbar discs. Interobserver agreement was fair to moderate in grading the lumbar muscles, whereas intra-observer agreement was almost perfect.
  
  
  CONCLUSIONS
  Convincing reliability was found in the evaluation of disc- and muscle-related MRI variables.
authors.affiliation: Back Research Center, Clinical Locomotion Science, University of Southern Denmark, Ringe, Denmark. joan@phvaldemar.dk
authors.forename: J
authors.initials: J
authors.lastname: Solgaard Sorensen
authors.forename: P
authors.initials: P
authors.lastname: Kjaer
authors.forename: Secher T
authors.initials: ST
authors.lastname: Jensen
authors.forename: P
authors.initials: P
authors.lastname: Andersen
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000175:diagnosis*; D008159:Lumbar Vertebrae; D008279:Magnetic Resonance Imaging; D008297:Male; D009135:Muscular Diseases / Q000175:diagnosis* / Q000209:etiology; D015588:Observer Variation; D015203:Reproducibility of Results