title: Intra- and inter-observer reliability of MRI examination of intervertebral disc abnormalities in patients with cervical myelopathy.
abstract: OBJECTIVE
  Intervertebral cervical disc herniation (CDH) is a relatively common disorder that can coexist with degenerative changes to worsen cervicogenic myelopathy. Despite the frequent disc abnormalities found in asymptomatic populations, magnetic resonance imaging (MRI) is considered excellent at detecting cervical spine myelopathy (CSM) associated with disc abnormality. The objective of this study was to investigate the intra- and inter-observer reliability of MRI detection of CSM in subjects who also had co-existing intervertebral disc abnormalities.
  
  
  METHODS
  Seven experienced radiologists reviewed twice the MRI of 10 patients with clinically and/or imaging determined myelopathy. MRI assessment was performed individually, with and without operational guidelines. A Fleiss Kappa statistic was used to evaluate the intra- and inter-observer agreement.
  
  
  RESULTS
  The study found high intra-observer percent agreement but relatively low Kappa values on selected variables. Inter-observer reliability was also low and neither observation was improved with operational guidelines. We believe that those low values may be associated with the base rate problem of Kappa.
  
  
  CONCLUSIONS
  In conclusion, this study demonstrated high intra-observer percent agreement in MR examination for intervertebral disc abnormalities in patients with underlying cervical myelopathy, but differing levels of intra- and inter-observer Kappa agreement among seven radiologists.
authors.affiliation: Center for Excellence in Surgical Outcomes, Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Andresa
authors.initials: A
authors.lastname: Braga-Baiak
authors.forename: Anand
authors.initials: A
authors.lastname: Shah
authors.forename: Ricardo
authors.initials: R
authors.lastname: Pietrobon
authors.forename: Larissa
authors.initials: L
authors.lastname: Braga
authors.forename: Arnolfo Carvalho
authors.initials: AC
authors.lastname: Neto
authors.forename: Chad
authors.initials: C
authors.lastname: Cook
mesh_terms: D000368:Aged; D002574:Cervical Vertebrae / Q000473:pathology*; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D017410:Practice Guidelines as Topic