TABLE 1.
Descriptive statistics for parent-reported sleep/wake parameters on scheduled and free days from the Children’s ChronoType Questionnaire (CCTQ) and linear regression coefficients by age (n = 152)
| Scheduled days* |
Free days* |
Statistics | Scheduled days† |
Free days† |
|
|---|---|---|---|---|---|
| Bedtime | 20:17 (0:31) | 20:47 (0:46) | p < 0.001, d = 0.77 | 0:09 (0:01)‡ | 0:16 (0:02)‡ |
| Time of lights-off | 20:35 (0:36) | 21:02 (0:48) | p < 0.001, d = 0.66 | 0:11 (0:02)‡ | 0:18 (0:02)‡ |
| Sleep latency | 0:12 (0:09) | 0:11 (0:10) | p ≤ 0.001, d = 0.07 | 0:01 (0:00:29) | |
| Sleep onset | 20:47 (0:38) | 21:13 (0:50) | p < 0.001, d = 0.59 | 0:13 (0:02)‡ | 0:19 (0:02)‡ |
| Wake-up time | 7:07 (0:25) | 7:51 (0:46) | p < 0.001, d = 1.23 | − 0:01 (0:01) | 0:09 (0:02)‡ |
| Get-up time | 7:16 (0:25) | 8:00 (0:48) | p < 0.001, d = 1.20 | −0:00:04(0:01) | 0:11 (0:02)‡ |
| Time fully alert | 7:29 (0:36) | 8:05 (0:53) | p < 0.001, d = 0.81 | − 0:01 (0:02) | 0:10 (0:03)‡ |
| Sleep period | 10:20 (0:40) | 10:38 (0:45) | p < 0.001, d = 0.43 | − 0:11 (0:02)‡ | |
| Time in bed | 10:59 (0:34) | 11:14 (0:47) | p < 0.001, d = 0.37 | − 0:10 (0:02)‡ | −0:05 (0:02)‡ |
| Sleep inertia | 0:22 (0:23) | 0:14 (0:20) | p < 0.001, d = 0.33 | 0:01 (0:01) | |
| Midsleep point | 1:58 (0:26) | 2:32 (0:43) | p < 0.001, d = 1.00 | 0:06 (0:01)‡ | 0:14 (0:02)‡ |
| MSFsc | 2:26 (0:40) | 0:13 (0:02)‡ | |||
*
Reported as mean (standard deviation), in hours:minutes
†
Reported as slope coefficient (standard error). When no interaction between age and type of day (scheduled versus free) existed, the common slope was reported (analysis of covariance); otherwise, separate slopes are reported.
‡
Significant effect of age (p ≤ .05)