Silicosis in the metal mining industry : a revaluation, 1958-1961.
- United States Public Health Service
- Date:
- [1964]
Licence: Public Domain Mark
Credit: Silicosis in the metal mining industry : a revaluation, 1958-1961. Source: Wellcome Collection.
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![he had a lower average code for smoking. The complete code for smoking which is used in this report is shown in table A.3; former smokers are given a relatively low value in the code. The lower aver- age smoking codes for workers with silicosis reflects the higher pro- portion of men among the silicotic groups than among the nonsilicotic group who reported having discontinued smoking. TABLE A.2.—Average values for 5 factors of metal mine workers 35 years and over with and without silicosis Smoking] Years in| Total Metal mine workers with— Number of | Height Age (code | under- | years workers | (inches) | (years) | from0 | ground in to 60) | mining | mining INOUSHICOSI G2. 2 °c Seek 7,404 | 68.9 | 46.2 | 32.4 | 11.4 16. 5 Sample ciliCOsis.. 2a So. ws oe 267 | 68.5 | 52.6 | 30.3 | 19.7 24. 9 Complicated silicosis. __._____--- 146 | 68.7 | 54.6 | 28.3 | 21.7 28. 6 TABLE A.3.—Classification of the cigarette smoking history among metal mine workers Code Definition 0 | Never smoked cigarettes. 10 | Former cigarette smoker (ceased smoking more than 1 year ago). 20 | Smoked for less than 10 years and now smokes less than % pack per day. 30 | Smoked for 10-24 years and now smokes less than % pack per day, or, smoked for less than 10 years and now smokes 4-1 pack per day. 40 | Smoked for 25 or more years and now smokes less than % pack per day, or smoked for 10-24 years and now smokes 4-1 pack per day, or smoked for less than 10 years and now smokes over 1 pack per day. 50 | Smoked for 25 or more years and now smokes 14-1 pack per day, or smoked for 10-24 years and now smokes over 1 pack per day. 60 | Smoked for 25 years or more and now smokes over 1 pack per day. Table A.4 compares the pulmonary function test results observed among mén with silicosis with test results which would be predicted from an analysis of the 7,404 active metal mine workers without sili- cosis. Predicted values were obtained in the following manner: The 7,404 metal mine workers with chest films that were negative for sili- cosis were used to establish a mathematical formula showing the simultaneous relation between pulmonary function and all five of the factors shown in table A.2, using a multiple regression technique. The resulting formulas are presented in table A.5. Only those coefficients that are statistically significant at the 1-percent level are shown in table A.5, which is discussed subsequently.](https://iiif.wellcomecollection.org/image/b32183136_0253.jp2/full/800%2C/0/default.jpg)
