The Japanese classification of computed tomography for pneumoconioses with standard films: Comparison with the ILO international classification of radiographs for pneumoconioses

Objective: Computed tomography (CT) has recently come to be used for personal diagnosis of pneumoconioses and preliminarily for epidemiological purposes. This study aimed to compare the diagnosis of pneumoconioses by the Japanese Classification of CT for Pneumoconioses (Hosoda-Shida Classification) with that by the ILO international Classification of Radiographs of Pneumoconioses (ILO 1980 standard). The Hosoda-Shida Classification is also described in this article. Subjects and Methods: CT and chest posterior-anterior X-ray (CXR) were performed in 21 subjects with an occupational history of mining, and 6 subject without exposure to any risk of pneumoconiosis. Three radiologists independently described the findings of CT and CXR according to both the Hosoda-Shida Classification and the ILO 1980 standard, respectively, Results. At least two of the three readers agreed in determining both the profusion and the type of small rounded opacities in 96% (26/27) of the CT films. The inter-reader agreement of profusion was satisfactory with the Cohen's weighted kappa value of 0.57 to 0.71. The weighted kappa for CXR and CT in describing the profusion and the type of small rounded opacities were 0.70 and 0.77, respectively. Conclusion: The Hosoda-Shida Classification for pneumoconioses is shown to be reliable and compatible with the ILO 1980 standard in describing the profusion and the type of small opacities.