Selection of reference films based on reliability assessment of a classification of high-resolution computed tomography for pneumoconioses.
OBJECTIVE
Worldwide demand has increased for the development of a computed tomography (CT) classification system that supplements the ILO classification of radiographs for pneumoconioses. The authors aimed to show preliminary reliability test results for selected referent films for the CT classification system developed through an international effort by researchers from seven countries.


METHODS
Reading trials by eight physicians who have considerable experience in pneumoconioses using a total of 114 lung zones consisting of 6 lung zones of 19 CT films of dust-exposed workers were performed to assess reliability of the classification system by weighted kappa. The results were also utilized for selecting reference films.


RESULTS
A good agreement was observed for both first and second reading trials for rounded opacities (weighted kappa=0.76, 0.74, first and second trial results, respectively), irregular opacities (0.60, 0.48), emphysema (0.56, 0.70) and honeycombing (0.72, 0.79). Ground glass opacities, on the other hand, showed moderate agreement (0.43, 0.38). Intra-reader agreements among eight readers were shown in the same table as the mean and standard deviation of weighted kappa statistics. The inter-reader agreement for pleural thickening was not as good as for parenchymal lesions.


CONCLUSIONS
The CT classification development may pioneer noble and sensitive medical screening for dust-exposed workers in selected settings. This system may be applied to radiographic borderline cases of profusion 0/1 and 1/0 by the ILO classification, in a setting that assures the occupational safety and health of workers exposed to some newly developed chemical compounds.
Suganuma
Narufumi
N
Division of Environmental Health, Department of International and Social Medicine, School of Medicine, University of Fukui, 23-3 Shimoaizuki, 910-1193 Matsuoka, Fukui, Japan. suganuma@fmsrsa.fukui-med.ac.jp
Kusaka
Yukinori
Y
Hering
K G
KG
Vehmas
T
T
Kraus
T
T
Parker
J E
JE
Shida
Hisao
H
D002965:Classification; D004391:Dust; D006801:Humans; D015588:Observer Variation; D016273:Occupational Exposure; D011009:Pneumoconiosis / Q000145:classification / Q000000981:diagnostic imaging*; D012015:Reference Standards; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000145:classification / Q000592:standards* / Q000706:statistics & numerical data
D004391:Dust