Table 3 General characteristics of the female workers
From: Comparison of sleep quality based on direction of shift rotation in electronics workers
| Â | Total | Forward rotation | Backward rotation | P value* |
|---|---|---|---|---|
Number of participants | 3001 | 2879 (95.9) | 122 (4.1) | Â |
Age, years | 27.0 ± 4.3 | 27.0 ± 4.3 | 27.0 ± 4.1 | 0.870 |
BMI, kg/m2 | 22.1 ± 4.1 | 22.1 ± 4.1 | 21.7 ± 3.4 | 0.357 |
Duration of shift work | Â | Â | Â | 0.034 |
 <5 years | 736 | 694 (94.3) | 42 (5.7) |  |
 5–9 years | 1324 | 1277 (96.5) | 47 (3.5) |  |
 ≥10 years | 941 | 908 (96.5) | 33 (3.5) |  |
Weekly working hours | Â | Â | Â | 0.051 |
 <41 h | 597 | 565 (94.6) | 32 (5.4) |  |
 41–51 h | 2168 | 2093 (96.5) | 75 (3.5) |  |
 52–59 h | 205 | 192 (93.7) | 13 (6.3) |  |
 ≥60 h | 31 | 29 (93.5) | 2 (6.5) |  |
Smoking status | Â | Â | Â | 0.900 |
 Non-smoker | 2703 | 2592 (95.9) | 111 (4.1) |  |
 Ex-smoker | 293 | 282 (96.2) | 11 (3.8) |  |
 Current smoker | 5 | 5 (100.0) | 0 (0.0) |  |
Alcohol consumption | Â | Â | Â | 0.497 |
 Non-drinker | 1512 | 1457 (96.4) | 55 (3.6) |  |
 Regular drinker | 1199 | 1145 (95.5) | 54 (4.5) |  |
 Heavy drinker | 290 | 277 (95.5) | 13 (4.5) |  |
Physical activity | Â | Â | Â | 0.592 |
 Sufficient exercise | 742 | 709 (95.6) | 33 (4.4) |  |
 Insufficient exercise | 2259 | 2170 (96.1) | 89 (3.9) |  |
Sleep duration, hours | 7.1 ± 1.6 | 7.2 ± 1.6 | 6.8 ± 1.5 | 0.037 |
PSQI score, points | 4.6 ± 2.8 | 4.5 ± 2.7 | 5.6 ± 2.8 | <0.001 |