Lung fibrosis - semiquantitative grading by Warrick et al.

Warrick classification of lung involvement in interstitial lung disease is a quantitative scoring method of disease extent and severity. The grading involves the following features of the disease:

Feature Grading
Global disease extent Estimated to the nearest 5%
Extent of reticulation Proportion of total disease extent
Extent of ground-glass Proportion of total disease extent
Coarseness of reticulation
  • normal: 0
  • fine intralobular fibrosis: 1
  • microcystic honeycombing: 2
  • macrocystic honeycombing: 3

The features are assessed at five levels:

  1. Origin of the great vessels
  2. Main carina
  3. Pulmonary venous confuence
  4. Halfway between levels 3 and 5
  5. Immediately above the right hemidiaphragm

Total disease extent corresponds to the mean of the percentage of disease at each level.


1. Warrick JH, Bhalla M, Schabel SI, Silver RM. High resolution computed
tomography in early scleroderma lung disease. J Rheumatol 1991;18:1520-28.
2. Assayag D., Kaduri S., Hudson M., Hirsch A., Barton M. High Resolution Computed Tomography Scoring Systems for Evaluating Interstitial Lung Disease in Systemic Sclerosis Patients. Rheumatology 2012;S1:003.
3. Sterclova M., Vasakova M. Quantification of parenchymal involvement in patients with fibrosing interstitial lung diseases. Ces Radiol 2013;67(3):204-208.