Table 2 Objective measures of sleep quantity and -quality indices across sex and day of the week
Sex | Day of the week | P-values | ||||
|---|---|---|---|---|---|---|
Female (n = 104) | Male (n = 41) | P-values | Weekday (n = 145) | Weekend (n = 145) | ||
Quantity | ||||||
Sleep time (minutes/day) | ||||||
Total | 458 (67) | 454 (105) | 0.8175 | 456 (86) | 458 (91) | 0.6828 |
Diurnala | 15 (37) | 20 (59) | 0.1560 | 10 (43) | 14 (39) | 0.6110 |
Nocturnal | 433 (60) | 410 (72) | 0.0464 | 427 (70) | 427 (76) | 0.9380 |
Nocturnal/Total sleep (%) | 95.0 (5.7) | 91.6 (9.9) | 0.0463 | 94.4 (7.7) | 93.8 (8.9) | 0.3553 |
Diurnal sleep time ≥ 1 minc | ||||||
Prevalenceb | 83.7 (87) | 80.5 (33) | 0.6495 | 54.0 (102) | 46.0 (87) | 0.0645 |
Duration (minutes)a | 56 (71) | 69 (73) | 0.0290 | 55 (73) | 64 (64) | – |
Sleep period starting between 00:01 and 05:59b | 34.6 (36) | 58.5 (24) | 0.0084 | 31.0 (45) | 20.7 (30) | 0.0443 |
Sleep period between 06:00 and 18:00b | 5.8 (6) | 9.8 (4) | 0.3935 | 4.1 (6) | 4.1 (6) | 1.0000 |
Clock time (hh:mm) | ||||||
In bed | 19:50 (2:03) | 18:14 (2:49) | 0.0016 | 19: 19 (2:53) | 19:31 (3:40) | 0.5725 |
Out of bed | 5:18 (1:10) | 5:50 (2:13) | 0.1544 | 5:28 (1:50) | 5:29 (1:43) | 0.8690 |
Sleep latency (minutes)a | 0.3 (0.7) | 0.5 (0.7) | 0.9440 | 0.4 (0.8) | 0.3 (1.0) | 0.6890 |
Sufficient sleep categoriesb | ||||||
Total sleep time | ||||||
<7 h/day | 33.7 (35) | 41.5 (17) | 0.6669 | 35.9 (52) | 40.0 (58) | 0.7647 |
7–9 h/day | 51.0 (53) | 43.9 (18) | 47.6 (69) | 44.1 (64) | ||
>9 h/day | 15.4 (16) | 14.6 (6) | 16.6 (24) | 15.9 (23) | ||
Nocturnal sleep time | ||||||
<7 h/night | 46.2 (48) | 56.1 (23) | 0.4904 | 47.6 (69) | 44.8 (65) | 0.6954 |
7–9 h/night | 50.0 (52) | 39.0 (16) | 48.3 (70) | 49.0 (71) | ||
>9 h/night | 3.8 (4) | 4.9 (2) | 4.1 (6) | 6.2 (9) | ||
Quality | ||||||
Wake after sleep onset (minutes) | 53 (16) | 44 (17) | 0.0022 | 51 (18) | 50 (20) | 0.8219 |
Number of awakenings | 15 (4) | 12 (4) | 0.0011 | 14 (5) | 14 (5) | 0.9577 |
Average awakening length (minutes) | 3.8 (1.0) | 4.1 (1.6) | 0.3339 | 4.0 (1.4) | 3.9 (1.5) | 0.5015 |
Sleep efficiency (%) | 87.7 (4.2) | 89.6 (4.5) | 0.0225 | 88.1 (4.6) | 88.4 (4.9) | 0.2440 |
Achieved ≥ 85% b | 79.8 (83) | 82.9 (34) | 0.6683 | 75.9 (110) | 76.6 (111) | 0.8903 |
Within-person sleep time SD (minutes)a | 85.1 (48.5) | 90.6 (80.9) | 0.2480 | 84.3 (60.8)d | 66.2 (63.2)d | – |
Movement index (%) | 15.5 (3.8) | 16.6 (3.6) | 0.1266 | 16.0 (4.0) | 15.5 (4.4) | 0.0617 |
Fragmentation index (%) | 11.0 (4.4) | 11.3 (4.2) | 0.7219 | 11.4 (4.7) | 10.7 (5.7) | 0.1755 |
Sleep fragmentation index (%) | 26.6 (7.1) | 27.9 (6.8) | 0.2986 | 27.4 (7.4) | 26.2 (8.7) | 0.0458 |
VM average counts | 34,847 (12,090) | 27,495 (10,686) | 0.0006 | 33,042 (13,162) | 31,966 (13,767) | 0.2951 |