Table 1. Study population characteristics.
| Characteristic | Questionnaire 1, n=263 | Questionnaire 2, n=418 |
|---|---|---|
| Sex* | ||
| Male | 261 (99) | 406 (97) |
| Female | 2 (1) | 12 (3) |
| Age (years)* | ||
| ≤49 | 14 (5) | 20 (5) |
| 50–59 | 59 (22) | 71 (17) |
| 60–69 | 126 (48) | 191 (46) |
| 70–80 | 64 (24) | 136 (32) |
| Race* a | ||
| White | 259 (98) | 391 (95) |
| Other | 4 (2) | 20 (5) |
| Education** | ||
| ≤High school | 99 (39) | 180 (44) |
| >High school | 131 (51) | 230 (56) |
| Refused | 27 (10) | 0 (0) |
| Smoking statusa | ||
| Current | 53 (21) | 86 (21) |
| Former | 147 (59) | 240 (58) |
| Never | 49 (20) | 87 (21) |
| Refused | 1 (<1) | 0 (0) |
| Worked on farm (years)b** | 23.9±19.7 | 29.4±18.6 |
| Agricultural exposures (yes/no) | ||
| Hogs, confinement | 58 (26) | 84 (20) |
| Hogs, open pen** | 115 (51) | 296 (71) |
| Beef cattle** | 136 (60) | 309 (74) |
| Dairy cattle** | 67 (30) | 243 (58) |
| Poultry** | 85 (38) | 286 (69) |
| Crops** | 155 (68) | 399 (96) |
| COPDa | ||
| Yes | 102 (42) | 151 (37) |
| No | 141 (58) | 257 (63) |
Data are presented as n (%).
*P<0.05, **P<0.001.
a
Numbers do not add up to 100% because of missing values.
b
Data presented as mean±SD.