| Study group characteristics | n (%) |
| Gender Male Female |
27 24.3 84 75.7 |
| Smoking No Yes |
88 79.3 23 20.7 |
| Energizing drinks No Yes |
48 43.2 63 56.8 |
| Irregular sleep No Yes |
44 39.6 67 60.4 |
| Sleepless nights No Yes |
65 58.6 46 41.4 |
| Afternoon nap No Yes |
75 67.6 36 32.4 |