| Variables | n | OR (Univariate analysis) | CI (95%) | p-value | OR (Multivariate analysis) | CI (95%) | p-value |
| Light | 300 - 500 lux 258/353 | 1 |
| 0.004 | 1 |
| 0.003 |
| ≥600 lux 156/247 | 1.72 | 1.1 - 2.5 |
| 1.8 | 1.2 - 2.6 |
| |
| Smartphone | No 131/218 | 1 |
| 0.02 | 1 |
| 0.02 |
| Yes 283/382 | 1.59 | 1.09 - 2.3 |
| 1.6 | 1.06 - 2.2 |
| |
| Videogames | No 309/470 | 1 |
| 0.001 | 1 |
| 0.0001 |
| Yes 105/130 | 2.55 | 1.5 - 4.2 |
| 2.6 | 1.6 - 4.3 |
| |
| Computer | No 175/280 | 1 |
| 0.0003 | 1 |
| 0.0001 |
| Yes 239/320 | 2.08 | 1.3 - 3.1 |
| 2.1 | 1.4 - 3.2 |
| |
| Position in the audience | 1st - 3rd row 183/256 | 1 |
| 0.06 | 1 |
| 0.09 |
| >4th row 231/344 | 0.68 | 0.4 - 1.02 |
| 0.7 | 0.4 - 1.05 |
| |
| Number of hours personal reading | 1 - 2 hours 205/304 | 1 |
| 0.05 | 1 |
| 0.08 |
| ≥3 hours 209/296 | 1.49 | 0.9 - 2.2 |
| 1.4 | 0.9 - 2.1 |
| |
| Mode of teaching | magistral 215/306 | 1 |
| 0.29 | 1 |
| 0.1 |
| power-point 199/294 | 0.81 | 0.5 - 1.1 |
| 0.7 | 0.5 - 1.2 |
|