|  | Firefighters | Farm Machinery Factory Workers | P-Values |
---|---|---|---|---|
Total (N) | Â | 371 | 81 | -- |
Noise level (dBA) | Mean Range | 76-79* | 82.45 | -- |
 |  | 68-115* | 67-98 |  |
Age at study initiation (2006) | Mean (S.D.) | 39.46 (6.89) | 44.98 (6.08) | < 0.0001 |
Alcohol (%) | Â | 222 | 50 | < 0.0001 |
   no |  | 40.2 | 38.3 |  |
   yes |  | 59.8 | 61.7 |  |
Smoking (%) | Â | 66 | 34 | < 0.0001 |
   no |  | 82.2 | 58 |  |
   yes |  | 17.8 | 42 |  |
Work period in months (2006) | Mean (SD) | 134.01 (90.34) | 256.20 (72.74) | < 0.0001 |
Duration of current employment | 0-10 years | 172 (46.36%) | 3 (3.7%) | -- |
 | 11-20 years | 155 (41.78%) | 35 (43.2%) |  |
 | > 20 years | 44 (11.86%) | 43 (53.1%) |  |
Shift length | Â | 9 or 15 | 8 or 10 | -- |