Table 4
Regression coefficients for adjusted lung function indices for subjects with age ≥18 years and history in coke ovens ≥1 year at the dates of last sets of lung function tests
| FEV1 (l) | FVC (l) | FEV1/FVC (%) | FEF25–75% (l/s) | |||||
|---|---|---|---|---|---|---|---|---|
| Coefficient | p value | Coefficient | p value | Coefficient | p value | Coefficient | p value | |
| *Limits of 95% CI for the parameter. | ||||||||
| †FEF25–75% was measured after January 1983, therefore the number of observations is smaller than that for FEV1, FVC and FEV1/FVC. | ||||||||
| Intercept | 3.70 (3.54 to 3.85)* | 0.0001 | 4.54 (4.37 to 4.70) | 0.0001 | 80.9 (78.6 to 83.1) | 0.0001 | 3.99 (3.46 to 4.52) | 0.0001 |
| Ex-smokers | 0.166 (0 to 0.331) | 0.0517 | 0.139 (−0.0376 to 0.315) | 0.126 | 2.62 (0.225 to 5.02) | 0.0334 | 0.272 (−0.166 to 0.710) | 0.230 |
| Duration of smoking for ex-smokers (years) | −0.0128 (−0.0200 to −0.0055) | 0.0006 | −0.00805 (−0.0157 to −0.00035) | 0.0420 | −0.253 (−0.358 to −0.148) | 0.0001 | −0.0358 (−0.0548 to −0.0167) | 0.0003 |
| Current smokers | −0.116 (−0.223 to −0.010) | 0.0341 | −0.0390 (−0.152 to 0.074) | 0.503 | −1.85 (−3.40 to −0.31) | 0.0195 | −0.304 (−0.643 to 0.035) | 0.0822 |
| Pack-years for current smokers | −0.000181 (−0.00285 to 0.00249) | 0.895 | −0.000550 (−0.00339 to 0.00229) | 0.706 | −0.0407 (−0.0793 to −0.00208) | 0.0404 | −0.0198 (−0.0310 to −0.0087) | 0.0006 |
| Operation | 0.0120 (−0.143 to 0.167) | 0.880 | −0.0707 (−0.235 to 0.094) | 0.403 | 1.74 (−0.49 to 3.98) | 0.129 | 0.0327 (−0.504 to 0.570) | 0.906 |
| Maintenance | −0.0164 (−0.154 to 0.121) | 0.816 | −0.0151 (−0.161 to 0.131) | 0.841 | 0.207 (−1.78 to 2.19) | 0.839 | 0.0869 (−0.399 to 0.573) | 0.729 |
| Electricity | −0.0359 (−0.187 to 0.115) | 0.644 | −0.0495 (−0.210 to 0.111) | 0.548 | −0.226 (−2.41 to 1.96) | 0.840 | −0.0429 (−0.575 to 0.489) | 0.876 |
| Work duration in “operation” (years) | −0.00945 (−0.0162 to −0.0027) | 0.0062 | −0.0116 (−0.0187 to −0.0044) | 0.0016 | −0.0856 (−0.183 to 0.012) | 0.0866 | −0.00239 (−0.0234 to 0.0186) | 0.825 |
| Work duration other than in “operation” (years) | −0.00206 (−0.00853 to 0.00441) | 0.536 | −0.00748 (−0.0144 to −0.0006) | 0.0344 | 0.0695 (−0.0241 to 0.163) | 0.149 | 0.00705 (−0.0133 to 0.0274) | 0.502 |
| R square | 0.0372 | 0.0358 | 0.0508 | 0.0811 | ||||
| No. of observations† | 834 | 833 | 833 | 500 | ||||
