Table 1 Sleep habits by bedtime
Whole | Up to 2100hG | 2100hG | 2130hG | 2200h or later G | F / χ 2 | p | |
|---|---|---|---|---|---|---|---|
Number of participants | 425 | 121 | 137 | 77 | 90 | ||
Bedtime (BT) (h) | 21.2 ± 0.9 | 20.2 ± 0.5 | 21.0 ± 0.1 | 21.5 ± 0.1 | 22.4 ± 0.6 | 649.293 | <0.001 |
Sleep onset latency (SOL) (min) | 29.9 ± 15.7 | 29.3 ± 14.4 | 30.7 ± 16.6 | 30.1 ± 14.7 | 29.1 ± 16.7 | 0.266 | 0.850 |
Sleep onset time (SOT) (h) | 21.7 ± 0.9 | 20.7 ± 0.5 | 21.5 ± 0.3 | 22.0 ± 0.2 | 22.9 ± 0.6 | 461.334 | <0.001 |
Wake time (WT) (h) | 7.2 ± 0.9 | 6.7 ± 0.6 | 7.0 ± 0.8 | 7.4 ± 0.6 | 7.9 ± 1.0 | 50.859 | <0.001 |
Time in bed (TIB) (h) | 10.0 ± 0.8 | 10.5 ± 0.7 | 10.0 ± 0.8 | 9.8 ± 0.6 | 9.5 ± 1.0 | 26.125 | <0.001 |
Total night sleep time (TST) (h) | 9.4 ± 0.9 | 9.9 ± 0.7 | 9.4 ± 1.0 | 9.2 ± 0.8 | 8.9 ± 1.0 | 22.193 | <0.001 |
Wake after sleep onset (WASO) (min) | 6.6 ± 21.4 | 5.3 ± 17.3 | 7.0 ± 27.1 | 7.7 ± 18.1 | 7.0 ± 19.6 | 0.247 | 0.864 |
Sleep efficiency (SE) (%) | 93.9 ± 4.6 | 94.5 ± 3.3 | 93.7 ± 5.5 | 93.6 ± 4.4 | 93.7 ± 4.6 | 1.040 | 0.375 |
Total daytime sleep time (NAP) (min) | 1.8 ± 0.7 | 1.6 ± 0.5 | 1.8 ± 0.8 | 1.9 ± 0.6 | 2.1 ± 0.6 | 7.078 | <0.001 |
Bedtime irregularity (%) | 41.9% | 33.1% | 38.7% | 49.4% | 52.2% | 10.163 | 0.017 |