Table 1.
Characteristics of the study population at baseline, N (%)
| Number of indivi(duals (%) | p Value | ||
| Non-night workers (n=7506) | Night workers (n=4816) | ||
| Age, years | 51.7 (4.7) | 51.2 (4.8) | <0.001 |
| Education | 0.06 | ||
| Compulsory | 3069 (41) | 2071 (43) | |
| More than compulsory | 4434 (59) | 2744 (57) | |
| Missing | 3 (0.04) | 1 (0.02) | |
| Children | 0.35 | ||
| Have children | 6122 (82) | 3960 (82) | |
| Do not have children | 1384 (18) | 856 (18) | |
| Missing | – | – | |
| Tobacco use | <0.001 | ||
| No | 919 (12) | 410 (8) | |
| Yes | 6506 (87) | 4359 (91) | |
| Missing | 81 (1) | 47 (1) | |
| Body mass index | <0.001 | ||
| Normal weight | 3570 (48) | 2099 (42) | |
| Underweight | 30 (0.4) | 10 (0.2) | |
| Overweight | 3325 (44) | 2278 (47) | |
| Obesity | 530 (7) | 500 (10) | |
| Missing | 51 (0.7) | 19 (0.4) | |
| Physical activity | 0.04 | ||
| Moderate | 1968 (26) | 1209 (25) | |
| Low | 2332 (31) | 1509 (31) | |
| High | 3192 (43) | 2077 (43) | |
| Missing | 14 (0.2) | 21 (0.4) | |
| Alcohol consumption | <0.001 | ||
| No alcohol | 147 (2) | 116 (2) | |
| Alcohol | 3343 (45) | 1954 (41) | |
| Missing | 4016 (53) | 2746 (57) | |
| Coffee consumption | <0.001 | ||
| No coffee | 471 (6) | 311 (6) | |
| 1–2 cups a day | 1298 (17) | 789 (16) | |
| 3–4 cups a day | 2595 (35) | 1437 (30) | |
| 5+ cups a day | 3140 (42) | 2272 (47) | |
| Missing | 2 (0.03) | 7 (0.2) | |
| Previous cancer | 0.14 | ||
| No | 7319 (98) | 4716 (98) | |
| Yes | 187 (2) | 100 (2) | |
| Missing | – | – | |
| New cancer diagnosis during follow-up | 0.16 | ||
| No cancer | 6870 (92) | 4419 (92) | |
| Prostate | 294 (4) | 160 (3) | |
| Other cancer | 342 (4) | 237 (5) | |
| Time to prostate cancer diagnosis (years(SD)) | 5.8 (2.7) | 6.1 (2.7) | 0.24 |
Significance levels based on t-tests or χ2 tests.