Table 2.
Distribution of International Labor Office classifications of large and small opacities for miners with a determination of PMF and an available chest radiograph in the Department of Labor clinical data
| Large Opacity Category* | n | % |
| A | 915 | 47 |
| B | 548 | 28 |
| C | 158 | 8 |
| No large opacity | 26 | 1 |
| Missing | 283 | 15 |
| Total: | 1,930 | |
|
Small Opacity Profusion Category† |
n | % |
| 0 | 4 | 0.2 |
| 1 | 645 | 40 |
| 2 | 762 | 47 |
| 3 | 205 | 13 |
| Missing | 5 | 0.3 |
| Total: | 1,621 | |
Definition of abbreviations: ILO = International Labor Office; PMF = progressive massive fibrosis.
*
Categories shown reflect categories of large opacities according to the ILO Classification of Radiographs for Pneumoconiosis.
†
Categories shown reflect major categories of small opacity profusion according to the ILO Classification of Radiographs for Pneumoconiosis. Small opacity profusion categories shown only for radiographs with large opacity categories indicating PMF (category A, B, or C; n = 1,621).