Interreader reliability for a new classification of lumbar disk disease.

J. G. Jarvik, D. R. Haynor, T. D. Koepsell, A. Bronstein, D. Ashley, R. A. Deyo

Research output: Contribution to journalArticlepeer-review

34 Scopus citations


RATIONALE AND OBJECTIVES: The nomenclature that divides disk herniations into protrusions and extrusions may increase the specificity of magnetic resonance (MR) imaging for clinically important lesions. Our goal was to determine this terminology's interreader reliability. METHODS: Three readers who were unaware of patients' histories independently read MR images of 34 consecutive patients with back pain. Readers classified disks at the lowest three lumbar levels as normal, bulging, protruded, or extruded. Kappa and weighted kappa values were the primary measures of agreement. RESULTS: Weighted kappa values showed fair-to-moderate agreement. Kappas for the dichotomous decision of extrusion present or absent were more variable, ranging from 0 to .78. Major disagreements (greater than a single category) occurred with 6.2% of all comparisons and in 10 of 34 volunteers; five involved extrusions. CONCLUSION: Overall, readers achieved moderate agreement for this new nomenclature. However, agreement for the presence or absence of an extrusion was less reliable.

Original languageEnglish (US)
Pages (from-to)537-544
Number of pages8
JournalAcademic radiology
Issue number7
StatePublished - Jul 1996
Externally publishedYes

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging


Dive into the research topics of 'Interreader reliability for a new classification of lumbar disk disease.'. Together they form a unique fingerprint.

Cite this