Table 4. School-related variables and risk of LBP using univariate logistic regression .
| % With LBP | OR | 95% CI | P | |
| Classroom furniture and layout design | ||||
| Seat height | ||||
| Just right | 32 | 1.0 | (Referent) | |
| Too high | 47 | 1.86 | (0.92–3.76) | 0.084 |
| Too low | 41 | 1.44 | (1.13–1.84) | 0.004 |
| Seat backrest height | ||||
| Just right | 33 | 1.0 | (Referent) | |
| Too high | 35 | 1.12 | (0.62–2.02) | 0.700 |
| Too low | 39 | 1.33 | (1.04–1.70) | 0.020 |
| Seat backrest inclination | ||||
| Just right | 32 | 1.0 | (Referent) | |
| Too high | 40 | 1.20 | (0.84–1.72) | 0.320 |
| Too low | 44 | 1.24 | (0.82–1.72) | 0.200 |
| Seat backrest curvature | ||||
| Just right | 31 | 1.0 | (Referent) | |
| Too curved | 44 | 1.74 | (1.18–2.57) | 0.010 |
| Too flat | 37 | 1.30 | (1.04–1.64) | 0.020 |
| Seat depth | ||||
| Just right | 33 | 1.0 | (Referent) | |
| Too deep | 35 | 1.08 | (0.64–1.81) | 0.078 |
| Too shallow | 39 | 1.31 | (1.01–1.70) | 0.040 |
| Seat width | ||||
| Just right | 33 | 1.0 | (Referent) | |
| Too wide | 43 | 1.60 | (0.93–2.35) | 0.069 |
| Too narrow | 38 | 1.26 | (0.98–1.62) | 0.075 |
| Desk height | ||||
| Just right | 32 | 1.0 | (Referent) | |
| Too high | 39 | 1.34 | (0.85–2.10) | 0.205 |
| Too low | 38 | 1.27 | (1.01–1.60) | 0.038 |
| Seat pan inclination | ||||
| Just right | 34 | 1.0 | (Referent) | |
| Too backward | 38 | 1.18 | (0.82–1.72) | 0.374 |
| Too forward | 37 | 1.17 | (0.78–1.76) | 0.454 |
| Seat-to-(black)board distance | ||||
| Just right | 31 | 1.0 | (Referent) | |
| Too near | 35 | 1.18 | (0.79–1.74) | 0.420 |
| Too far | 44 | 1.69 | (1.32–2.18) | 0.001 |
| Viewing the (black)board | ||||
| Very easy | 27 | 1.0 | (Referent) | |
| Neutral | 40 | 1.82 | (1.54–2.27) | 0.001 |
| Very difficult | 43 | 2.03 | (1.46–2.83) | 0.001 |
| Homework | ||||
| Just right | 30 | 1.0 | (Referent) | |
| Not enough | 40 | 1.35 | (0.90–1.74) | 0.186 |
| Too much | 41 | 1.63 | (1.28–2.07) | 0.001 |
| Schoolbag carriage variables | ||||
| Type of schoolbag | ||||
| Backpack | 34 | 1.0 | (Referent) | |
| Briefcase | 33 | 0.94 | (0.72–1.25) | 0.690 |
| Shoulder bag | 42 | 1.37 | (0.85–2.22) | 0.200 |
| Schoolbag weight (as % body weight) | ||||
| ≤10% | 31 | 1.0 | (Referent) | |
| >10% | 33 | 1.14 | (0.69–1.87) | 0.610 |
| Time spent carrying schoolbag (min/day) | ||||
| ≤30 | 30 | 1.0 | (Referent) | |
| 30–60 | 35 | 1.27 | (0.98–1.64) | 0.071 |
| >60 | 43 | 1.77 | (1.35–2.33) | 0.001 |
| Method of schoolbag carriage | ||||
| Both shoulders | 32 | 1.0 | (Referent) | |
| One shoulder | 38 | 1.31 | (1.05–1.64) | 0.020 |
| By hands | 30 | 0.92 | (0.64–1.32) | 0.640 |
| Method of travel to/from school | ||||
| Bus/car/Bike | 32 | 1.0 | (Referent) | |
| Walk | 35 | 0.87 | (0.69–1.11) | 0.269 |
Abbreviations: LBP, low back pain; OR, odds ratio.