Table 1 Descriptive characteristics of participants by case/control status at start of follow-up. Frequency (percentage) or Mean (SD)
From: Alternative duty work as workplace-initiated procedure to reduce sickness absence
|  | City A: Alternative duty work in use in 2014 | Control Cities |  | City D: Alternative duty work in use in 2016 | Control Cities |  |
|---|---|---|---|---|---|---|
|  | Case 43% (n = 5341) | Control 57% (n= 6976) | P for difference | Case 53% (n= 7538) | Control 47% (n= 6720) | P for difference |
Sex: Men | 1486 (28) | 1633 (23) | Â | 2299 (31) | 1530 (23) | Â |
Women | 3855 (72) | 5343 (77) | < 0.001 | 5239 (69) | 5190 (77) | < 0.001 |
Employment contract | ||||||
 Permanent | 4485 (84) | 5746 (82) |  | 6650 (88) | 5600 (83) |  |
 Temporary | 833 (16) | 1161 (17) |  | 866 (11) | 1069 (16) |  |
 Other | 23 (0.4) | 69 (1) | < 0.001 | 22 (0.3) | 51 (1) | < 0.001 |
Occupational class | ||||||
 Elementary workers | 259 (5) | 371 (5) |  | 461 (6) | 337 (5) |  |
 Skilled manual | 1735 (33) | 2257 (33) |  | 2454 (33) | 2127 (32) |  |
 Lower grade non-manual | 1338 (25) | 1640 (24) |  | 1438 (19) | 1504 (23) |  |
 Managers and professionals | 2000 (37) | 2661 (38) | 0.20 | 3160 (42) | 2673 (40) | < 0.001 |
Age: mean (SD) | 45.9 (8.8) | 46.0 (9.3) | Â | 45.6 (9.3) | 46.0 (9.4) | Â |