Time at measurement | Variable | Â | Cases without LBP (n = 1111) | % | Cases with previous LBP (n = 1566) | % |
---|---|---|---|---|---|---|
Baseline | Age | Â | Â | Â | Â | Â |
 |  | < 20 | 68 | 6.1 | 91 | 5.8 |
 |  | 20-29 | 331 | 29.8 | 497 | 31.7 |
 |  | 30-39 | 309 | 27.8 | 437 | 27.9 |
 |  | 40-49 | 292 | 26.3 | 384 | 24.5 |
 |  | >50 | 111 | 10 | 157 | 10 |
Baseline | Education | Â | Â | Â | Â | Â |
 |  | Health care helper | 741 | 66.7 | 972 | 62.1 |
 |  | Health care assistant | 370 | 33.3 | 594 | 37.9 |
Baseline | Foreign background | Â | Â | Â | Â | Â |
 |  | Born in Denmark | 962 | 86.6 | 1413 | 90.2 |
Baseline | Living status | Â | Â | Â | Â | Â |
 |  | Living with partner | 131 | 12 | 141 | 9.1 |
 |  | Living with spouse/partner |  |  |  |  |
 |  |  | 734 | 76 | 1058 | 75.2 |
Baseline | Children living at home | Â | Â | Â | Â | Â |
 |  | No | 504 | 45.7 | 754 | 48.6 |
 |  | 1 child | 213 | 19.3 | 289 | 18.6 |
 |  | 2 children | 257 | 23.3 | 351 | 22.6 |
 |  | 3 or more children | 128 | 11.6 | 159 | 10.2 |
Baseline | Musculoskeletal disorder previous 12 months | Â | Â | Â | Â | Â |
 |  | Low back | - | - | 1349 | 88.2 |
 |  | Upper back | 230 | 20.8 | 584 | 37.8 |
 |  | Neck | 682 | 61.9 | 1052 | 67.5 |
 |  | Shoulder | 356 | 32.1 | 798 | 51.3 |
Follow-up | Days with low back pain previous 12 months | Â | Â | Â | Â | Â |
 |  | No pain | 586 | 53 | 331 | 21.3 |
 |  | 1-7 days | 269 | 24.3 | 404 | 26 |
 |  | 8-30 days | 162 | 14.6 | 444 | 28.5 |
 |  | > 30 days | 89 | 8 | 377 | 24.3 |
Follow-up | Body mass index | Â | Â | Â | Â | Â |
 |  | < 18.5 | 19 | 3.2 | 27 | 2.8 |
 |  | 18.5-24.9 | 419 | 60 | 533 | 57.4 |
 |  | 25.0-29.9 | 188 | 27.3 | 270 | 27.7 |
 |  | ≥ 30 | 85 | 9.6 | 153 | 12.2 |
Follow-up | Smoking | Â | Â | Â | Â | Â |
 |  | Current smoker | 429 | 38.9 | 682 | 43.9 |
 |  | Ex-smoker | 227 | 20.6 | 333 | 21.4 |
 |  | Never smoked | 446 | 40.5 | 538 | 34.6 |
Follow-up | Leisure time physical activity | Â | Â | Â | Â | Â |
 |  | Sedentary | 77 | 7.1 | 137 | 8.9 |
 |  | Light | 570 | 52.4 | 778 | 50.5 |
 |  | Moderate | 377 | 34.7 | 540 | 35.1 |
 |  | High | 64 | 5.9 | 85 | 5.5 |