Table 1.
Descriptive statistics of the study population by case/control group status, n (%)
| Total population (n = 9720) | Employees with reduced work ability (n = 683) | |||||||
|---|---|---|---|---|---|---|---|---|
| Cases (n = 4120) | Controls (n = 5600) | p for difference | Cases (n = 281) | Controls (n = 402) | p for difference | |||
| Sex | < 0.001 | 0.43 | ||||||
| Men | 697 (17) | 1243 (22) | 70 (25) | 111 (28) | ||||
| Women | 3423 (83) | 4357 (78) | 211 (75) | 291 (72) | ||||
| Mean age (SD) | 47.7 (8.9) | 48.1 (8.7) | 0.01 | 49.9 (8.2) | 50.8 (7.3) | 0.14 | ||
| Occupational class | < 0.001 | 0.001 | ||||||
| High | 2403 (60) | 3221 (60) | 176 (65) | 223 (57) | ||||
| Intermediate | 344 (9) | 1031 (19) | 42 (16) | 108 (28) | ||||
| Low | 1212 (31) | 1161 (21) | 50 (19) | 59 (15) | ||||
| Job contract | < 0.001 | < 0.001 | ||||||
| Permanent | 3668 (89) | 5526 (99) | 261 (93) | 399 (99) | ||||
| Temporary | 452 (11) | 66 (1) | 20 (7) | 3 (1) | ||||
| Smoking | 0.22 | 0.12 | ||||||
| Yes | 550 (14) | 799 (14) | 55 (20) | 98 (25) | ||||
| Drinking | 0.34 | 0.98 | ||||||
| No | 693 (17) | 971 (17) | 57 (20) | 82 (20) | ||||
| Moderate | 3028 (74) | 4133 (74) | 187 (67) | 265 (66) | ||||
| Heavy | 399 (9) | 496 (9) | 37 (13) | 55 (14) | ||||
| Physically inactive | ||||||||
| Yes | 1009 (25) | 1532 (27) | 0.001 | 119 (42) | 188 (47) | 0.23 | ||
| Psychiatric distress | ||||||||
| Yes | 947 (23) | 1234 (22) | 0.27 | 167 (59) | 227 (57) | 0.46 | ||
| Sickness absence of > 30 days (in 2 years pre-intervention) | ||||||||
| Yes | 370 (9) | 89 (2) | < 0.001 | 59 (21) | 13 (3) | < 0.001 | ||
| Pooled mean number* (SD) of sickness absence days | ||||||||
| Three years before | 12.5 (14.4) | 16.3 (21.3) | 23.6 (20.3) | 30.0 (32.9) | ||||
| Three years after | 13.8 (20.4) | 16.0 (22.0) | 24.8 (29.4) | 29.3 (32.3) | ||||
*Pooled mean = (Total number of sickness absence days year 1 + total number of sickness absence days year 2 + total number of sickness absence days year 3)/3