Table 4.
Frequency distribution of health-related characteristics and outcomes by main and supplementary independent variables.
| Characteristic | History of work-related low back injury | History of time off or light duties due to work-related low back injury | ||
| Yes | No | Yes | No | |
| Smoking – N (%) | ||||
| Never smoked | 184 (46.1) | 352 (54.1) | 111 (42.5) | 424 (54.0) |
| Past smoker | 94 (23.6) | 158 (24.3) | 70 (26.8) | 180 (22.9) |
| Current smoker | 121 (30.3) | 141 (21.7) | 80 (30.7) | 181 (23.1) |
| BMI weight categories (kg/m2) – N (%) | ||||
| <18.5 (underweight) | 17 (4.1) | 31 (4.6) | 11 (4.0) | 37 (4.6) |
| 18.5–24.9 (normal) | 150 (36.3) | 271 (40.3) | 93 (34.2) | 325 (40.1) |
| 25.0–29.9 (overweight) | 175 (42.4) | 258 (38.3) | 121 (44.5) | 311 (38.4) |
| ≥ 30.0 (obese) | 71 (17.2) | 113 (16.8) | 47 (17.3) | 137 (16.9) |
| General health from SF-36 – mean (SD) | 62.8 (13.7) | 64.8 (14.0) | 61.8 (13.4) | 64.8 (14.0) |
| Days of exercise per week – mean (SD) | 2.9 (2.2) | 2.7 (2.1) | 2.9 (2.2) | 2.8 (2.1) |
| Life satisfaction | ||||
| Very satisfied | 81 (19.9) | 182 (27.5) | 47 (17.5) | 216 (27.2) |
| Satisfied | 211 (51.8) | 327 (49.5) | 134 (49.8) | 402 (50.6) |
| Neither satisfied nor dissatisfied | 76 (18.7) | 102 (15.4) | 62 (23.1) | 114 (14.3) |
| Dissatisfied | 32 (7.9) | 38 (5.8) | 25 (9.3) | 45 (5.7) |
| Very dissatisfied | 7 (1.7) | 12 (1.8) | 1 (0.4) | 18 (2.3) |
| Outcome | ||||
| Low back pain | ||||
| Absent | 48 (11.8) | 249 (37.7) | 30 (11.2) | 267 (33.5) |
| Low intensity/low disability | 221 (54.3) | 292 (44.2) | 133 (49.8) | 378 (47.5) |
| High intensity/low disability | 65 (16.0) | 68 (10.3) | 42 (15.7) | 90 (11.3) |
| High disability | 73 (17.9) | 51 (7.7) | 62 (23.2) | 61 (7.7) |
| Depressive symptomatology | ||||
| CES-D score <16 | 300 (75.8) | 511 (80.0) | 193 (74.2) | 617 (79.9) |
| CES-D score ≥ 16 | 96 (24.2) | 128 (20.0) | 67 (25.8) | 155 (20.1) |