Table 4.
Correlations between main study variables.
| IV | IS | RA | Acroph. | SD | PS | Depr. | Fatigue | SQ | |
|---|---|---|---|---|---|---|---|---|---|
| IV | −0.579 * | −0.626 * | −0.095 | 0.332 | −0.534 * | −0.097 | −0.055 | −0.367 | |
| IS | −0.579 * | 0.478 ° | −0.405 | 0.240 | 0.101 | 0.046 | 0.085 | 0.309 | |
| RA | −0.626 * | 0.478 ° | −0.319 | 0.042 | 0.187 | 0.108 | 0.097 | 0.235 | |
| Acroph. | −0.095 | −0.405 | −0.319 | −0.582 * | 0.209 | 0.379 | 0.102 | 0.353 | |
| SD | 0.332 | 0.240 | 0.042 | −0.582 * | −0.670 ** | 0.111 | 0.130 | −0.041 | |
| PS | −0.534 * | 0.101 | 0.187 | 0.209 | −0.670 ** | 0.202 | −0.133 | 0.244 | |
| Depr. | −0.097 | 0.046 | −0.108 | 0.379 | 0.111 | −0.202 | 0.546 * | 0.323 | |
| Fatigue | −0.055 | 0.085 | 0.097 | −0.102 | 0.130 | −0.133 | 0.546 * | 0.195 | |
| SQ | −0.367 | 0.309 | 0.235 | 0.353 | −0.041 | 0.244 | 0.323 | 0.195 |
Spearman’s ρ correlation coefficients (N = 14) between intradaily variability (IV), interdaily stability (IS), relative amplitude (RA), acrophase (Acroph.), nocturnal sleep duration (SD), processing speed (PS), depression (Depr.), fatigue, and sleep quality (SQ). High values of sleep quality indicate low sleep quality. ° p ≤ 0.1; * p ≤ 0.05; ** p ≤ 0.01.