Table 4
Total hours of sleep (mean SD) before day and night shifts, and hours of wakefulness before the start of the shift
| Day shift 1 | Day shift 2 | Night shift 1 | Night shift 2 | |
| Total sleep time: | ||||
| Young | 4.17 (0.2) | 5.8 (0.18) | 5.5 (0.2) | 7.38 (0.2) |
| Older | 4.14 (0.15) | 5.38 (0.14) | 5.73 (0.13) | 6.01 (0.2) |
| p Value young volder | NS | NS | NS | 0.0003 |
| Earlier wakefulness: | ||||
| Young | 0.84 (0.01) | 0.89 (0.01) | 12.71 (0.07) | 2.3 (0.25) |
| Older | 0.85 (0.02) | 0.93 (0.03) | 12.73 (0.09) | 3.14 (0.26) |
| p Value young volder | NS | NS | NS | 0.02 |
