title: Factors influencing the reading of small irregular opacities in a radiological survey of asbestos miners in South Africa.
abstract: A cross-sectional radiological survey of 2,245 men who were employed in South African asbestos mines was conducted in 1976. Since 1976, the lungs of 172 of these men who died have been examined to establish the presence of asbestosis or other pneumoconiosis. The x-ray readings (ILO/UC 1971) were compared with the pathological findings. A high prevalence of false positive readings, particularly for two of the three readers, was found. False negative readings were also very prevalent. Detailed information about asbestos and other mining exposure, smoking habit, age, height, and weight were examined to determine what influence they may have had in inducing false positive findings. Other dust exposure and smoking appeared to be possible factors, whereas age and obesity were probably not. It is suggested that the term "small irregular opacities" requires more precise definition.
authors: Epidemiology Research Unit, Medical Bureau for Occupational Diseases, Johannesburg, South Africa.
authors: G K
authors: GK
authors: Sluis-Cremer
authors: P A
authors: PA
authors: Hessel
authors: E
authors: E
authors: Hnizdo
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001195:Asbestosis / Q000000981:diagnostic imaging* / Q000473:pathology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D005189:False Positive Reactions; D006046:Gold; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008906:Mining; D011009:Pneumoconiosis / Q000000981:diagnostic imaging / Q000473:pathology; D011859:Radiography; D013019:South Africa
chemical_list: D006046:Gold