Method for minimizing observer variation for the quantitation of high-resolution computed tomographic signs of lung disease

J Comput Assist Tomogr. Sep-Oct 2011;35(5):596-601. doi: 10.1097/RCT.0b013e3182277d05.

Abstract

Objectives: This study aimed to describe a method of reducing interobserver variation associated with the visual quantitation of high-resolution computed tomographic (HRCT) signs of airways and interstitial lung disease (ILD).

Methods: The HRCT scans of 2 cohorts of patients with airways disease (n = 144) and ILD (n = 109) were evaluated by 2 observers. Selected signs of airways disease were evaluated: (1) bronchial wall thickness and (2) the extent of the decreased attenuation. In the ILD group, the total extent of disease was scored. These 3 HRCT signs were scored by 2 observers independently using a standard method. The observers rescored the CT scans with a new scoring system (continuous learning method, CLM).

Results: Observer agreement for CT signs was superior for CLM: bronchial wall thickness κw increased from 0.51 to 0.76; for decreased attenuation, κw increased from 0.34 to 0.81; and for ILD extent, κw increased from 0.53 to 0.87.

Conclusions: The CLM reduces noise from observer variation in studies that require visual quantitation of HRCT signs of lung disease.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Child
  • Cohort Studies
  • Female
  • Humans
  • Lung Diseases, Interstitial / diagnostic imaging*
  • Lung Diseases, Interstitial / pathology
  • Male
  • Middle Aged
  • Observer Variation
  • Radiographic Image Interpretation, Computer-Assisted
  • Reproducibility of Results
  • Respiratory Function Tests
  • Tomography, X-Ray Computed / methods*