A pilot study to evaluate Japanese standard radiographs of pneumoconioses (1982) according to the ILO 1980 International Classification of Radiographs of Pneumoconioses.

The Japanese Classification of Radiographs of Pneumoconioses (JC) is characterized by its own standard films, including limit films which are defined to represent the upper limit of category 0 or the lower limit of category 1. This pilot study was aimed at evaluating the JC standard radiographs according to the ILO 1980 International Classification of Radiographs of Pneumoconioses (IC) in which some of the JC standards were read according to the IC by two groups of experienced British workers, four non-medically qualified (NM panel) and six medically qualified (MQ panel). The Japanese standard limit films, with rounded opacities of category 0/1 or 1/0, were classified by both groups as having lower categories in the IC than in the JC. With the standard mid-category films showing rounded or irregular opacities, the NM panel tended to produce higher categories than the MQ panel. From reading results by both panels, however, it may be said that the JC mid-category standards agree with the IC in terms of category.