Table 3.
Bivariate analysis of the incidence of low back pain with electronic devices in high school adolescents.
| Factor | Incidence of low back pain |
|||
|---|---|---|---|---|
| Total | n | % | OR (95%CI) | |
| Television | ||||
| Watch television | ||||
| No | 119 | 23 | 16.1 | 1.00 |
| Yes | 638 | 120 | 83.9 | 0.97 (0.65, 1.45) |
| Frequency (times/week) | ||||
| Up to 2 times | 453 | 35 | 24.5 | 1.00 |
| 3 times or more | 185 | 85 | 59.4 | 1.019 (0.71, 1.44) |
| Daily time (hours/day) | ||||
| Less than 3 h | 366 | 48 | 33.6 | 1.00 |
| 3 h or more | 272 | 72 | 50.3 | 0.90 (0.65, 1.25) |
| Computer | ||||
| Use computer | ||||
| No | 195 | 35 | 24.5 | 1.00 |
| Yes | 562 | 108 | 75.5 | 1.07 (0.75, 1.51) |
| Type | ||||
| Desktop | 288 | 47 | 37.1 | 1.00 |
| Laptop | 236 | 53 | 5.6 | 1.37 (0.96, 1.95) |
| Desktop and Laptop | 38 | 8 | 32.9 | 1.29 (0.66, 2.51) |
| Height of the screen | ||||
| Eyes above the midpoint | 140 | 23 | 16.1 | 1.00 |
| Eyes at the midpoint | 366 | 77 | 53.8 | 1.28 (0.83, 1.95) |
| Eyes below the midpoint | 56 | 8 | 5.6 | 0.86 (0.41, 1.82) |
| Eye-to-screen distance | ||||
| Up to 30 cm | 375 | 72 | 50.3 | 1.00 |
| 30 cm or more | 187 | 36 | 25.2 | 1.00 (0.69, 1.43) |
| Frequency (times/week) | ||||
| Up to 2 times | 250 | 54 | 37.8 | 1.00 |
| 3 times or more | 312 | 54 | 37.8 | 1.24 (0.88, 1.75) |
| Daily time (hours/day) | ||||
| Less than 3 h | 304 | 48 | 33.6 | 1.00 |
| 3 h or more | 258 | 60 | 42.0 | 1.06 (0.75, 1.49) |
| Mobile phone | ||||
| Use mobile phone | ||||
| No | 24 | 8 | 5.6 | 1.00 |
| Yes | 733 | 135 | 94.4 | 1.81 (1.01, 3.33) |
| Posture while using mobile phone* | ||||
| Standing | 287 | 60 | 42.0 | 1.29 (0.95, 1.75) |
| Sitting | 432 | 87 | 60.8 | 1.26 (0.91, 1.73) |
| Lying of prone | 461 | 93 | 65.0 | 1.30 (0.93, 1.82) |
| Semi-lying | 255 | 55 | 38.5 | 1.28 (0.94, 1.75) |
| Daily time (hours/day) | ||||
| Less than 3 h | 188 | 26 | 18.2 | 1.00 |
| 3 h or more | 545 | 109 | 76.9 | 1.44 (0.97, 2.14) |
| Eye-to-screen distance | ||||
| Up to 20 cm | 632 | 118 | 82.5 | 1.00 |
| 20 cm or more | 101 | 17 | 11.9 | 0.90 (0.56, 1.43) |
| Tablet | ||||
| Use tablet | ||||
| No | 657 | 125 | 87.4 | 1.00 |
| Yes | 100 | 18 | 12.6 | 0.94 (0.60, 1.47) |
| Posture while using tablet* | ||||
| Standing | 28 | 8 | 5.6 | 2.05 (0.90, 4.67) |
| Sitting | 61 | 15 | 10.5 | 3.19 (0.98, 10.32) |
| Lying of prone | 51 | 12 | 8.4 | 1.92 (0.78, 4.71) |
| Semi-lying | 26 | 6 | 4.2 | 1.42 (0.59, 3.40) |
| Daily time (hours/day) | ||||
| Less than 3 h | 77 | 15 | 10.5 | 1.00 |
| 3 h or more | 23 | 3 | 2.1 | 0.66 (0.21, 2.11) |
| Eye-to-screen distance | ||||
| Up to 20 cm | 85 | 15 | 10.5 | 1.00 |
| 20 cm or more | 15 | 3 | 2.1 | 1.13 (0.37, 3.44) |
⁎
In the questions the participants could choose more than one option. CI, confidence interval; OR, odds ratio.