Table 1.
Descriptive characteristics of groups.
| Variable | Active wake group (N = 25) Mean (SD) | Quiet rest group (N = 26) Mean (SD) | Nap group (N = 27) Mean (SD) | p-value |
|---|---|---|---|---|
| Age (years) | 22.08 (2.04) | 22.00 (1.94) | 21.15 (1.83) | p = 0.16 |
| Gender (male, %) | 28% | 22% | 27% | p = 0.88 |
| GSQS | 1.96 (1.72) | 2.31(2.13) | 2.33 (1.96) | p = 0.75 |
| Stress scale (before the Learning phase) | 2.65 (2.09) | 2.55 (1.43) | 3.33 (1.98) | p = 0.35 |
| Stress scale (before the Retesting phase) | 2.59 (1.28) | 2.00 (1.33) | 1.77 (1.41) | p = 0.17 |
| KSS (before the Learning phase) | 6.44 (1.26) | 6.81 (1.13) | 6.19 (1.52) | p = 0.24 |
| KSS (before the Retesting phase) | 5.64 (1.19) | 5.96 (1.70) | 6.62 (1.30) | p = 0.05 |
| Digit span | 6.32 (1.31) | 5.88 (1.14) | 6.26 (1.06) | p = 0.36 |
| Counting span | 3.91 (1.50) | 3.59 (0.72) | 3.48 (0.81) | p = 0.33 |
| WCST – number of perseverative errors | 15.67 (9.23) | 14.31 (3.23) | 13.19 (5.86) | p = 0.40 |
GSQS, Groningen Sleep Quality Scale; KSS, Karolinska Sleepiness Scale; WCST, Wisconsin Card Sorting Test. Higher scores in the KSS indicate lower sleepiness.