Table 4.
Group differences for early/normal/late chronotype and lesser/greater sleep discrepancy (SD).
| Nominal Data (Y/N) | Interval Data (mean ± std. dev.) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
|
| ||||||||||
| Diff. falling asleep? | Diff. staying asleep? | Refresh. sleep? | Bothered during night? | Rep. sleep duration | Total sleep time | % Deep sleep | % REM sleep | WASO | ||
| Chronotype | Early | 1/3 | 3/1 | 3/1 | 1/1 | 1.78 ± 0.15 | 419.10 ± 30.81 | 1.78 ± 0.15 | 22.85 ± 3.43 | 1.78 ± 0.15 |
| Normal | 1/2 | 1/1 | 1/1 | 1/5 | 6.33 ± 0.36 | 396.50 ± 21.74 | 19.66 ± 3.98 | 28.53 ± 3.84 | 2.00 ± 0.55 | |
| Late | 1/1 | 7/3 | 4/1 | 1/4 | 6.70 ± 0.34 | 1.30 ± 0.15 | 19.10 ± 1.94 | 1.30 ± 0.15 | 3.00 ± 0.62 | |
|
| ||||||||||
| p-value | 0.72 | 0.70 | 0.47 | 0.52 | 0.62 | 0.79 | 0.96 | 0.60 | 0.47 | |
|
| ||||||||||
| SD | Lesser | 4/8 | 7/5 | 6/6 | 3/9 | 6.75 ± 0.99 | 430.00 ± 76.19 | 17.41 ± 7.23 | 23.35 ± 8.70 | 2.25 ± 1.48 |
| Greater | 4/4 | 6/2 | 8/0 | 2/6 | 6.19 ± 0.97 | 375.50 ± 60.99 | 21.9 ± 9.80 | 29.88 ± 12.35 | 2.75 ± 1.88 | |
|
| ||||||||||
| p-value | 0.65 | 0.64 | 0.042* | 1.00 | 0.24 | 0.13 | 0.28 | 0.21 | 0.56 | |
Note:
a
Nominal (Y/N) data is reported as frequencies while interval data is reported as mean (standard deviation).
For comparing early/normal/late chronotype groups, nominal data was analyzed using a Chi-square test for association and interval data was analyzed using one-way ANOVA. When assessing lesser/greater SD groups, nominal data was analyzed using Fisher’s exact test and interval data was analyzed using Student’s t-test. (*p < 0.05). Abbreviations are as follows: diff. = difficulty, refresh. = refreshing.