Demographics and characteristics of active underground Kentucky, Virginia and West Virginia coal miners participating in Enhanced Coal Workers’ Health Surveillance Program (ECWHSP), September 2005 to December 2012, n=3771
| Characteristics | Small mine (n=908) | Large mine (n=2863) | p Value |
|---|---|---|---|
| Sex, n male (%) | 906 (99.8) | 2849 (99.5) | 0.44 |
| Race, n white (%) | 901 (99.2) | 2820 (98.6) | 0.09 |
| Ever smoker (%) | 507 (56.1) | 1409 (49.4) | <0.01 |
| Age, mean (SD) | 45.8 (10.4) | 46.8 (10.5) | 0.02 |
| UG tenure, mean (SD) | 20.9 (11.6) | 21.0 (12.0) | 0.73 |
| BMI, mean (SD) | 29.9 (5.2) | 30.3 (5.0) | 0.04 |
BMI, body mass index; n, number; UG, underground.