Table 2.
Sample median values of study variables per condition and Wilcoxon signed rank tests.
| Sleep and Rest-Activity (n = 14) | Control Condition | Experimental Condition | Wilcoxon Signed Rank Test |
|---|---|---|---|
| 24-h Sleep Duration (Minutes) | 444.68 | 430.24 | z = −0.23, p = 0.814 |
| Sleep Duration (Minutes) | 406.50 | 407.24 | z = −0.53, p = 0.594 |
| Sleep Latency (Minutes) | 20.88 | 15.66 | z = −0.34, p = 0.730 |
| Wake After Sleep Onset (Minutes) | 77.11 | 81.11 | z = −0.28, p = 0.778 |
| Sleep Efficiency | 77.78 | 76.41 | z = −0.09, p = 0.925 |
| Acrophase | 13.13 | 13.23 | z = −0.53, p = 0.594 |
| Relative Amplitude (RA) | 0.74 | 0.76 | z = -1.02, p = 0.308 |
| Intradaily Variability (IV) | 1.00 | 1.10 | z = −0.59, p = 0.552 |
| Interdaily Stability (IS) | 0.57 | 0.51 | z = −0.35, p = 0.972 |
| Cognitive Batteries | |||
| Pattern Comparison and Processing Speed Test (Raw score; n = 12) | 32 | 30 | z = −0.08, p = 0.937 |
| Flanker Inhibitory Control and Attention Test (Computed Score; n = 9) | 7.14 | 7.14 | z = −1.12, p = 0.260 |
| Dimensional Change Card Sort Test (Computed Score; n = 9) | 6.27 | 6.39 | z = −0.41, p = 0.678 |
| Geriatric Depression Total Score (n = 13) | |||
| None (0–4) | 9 | 8 | |
| Mild (5–8) | 3 | 5 | |
| Moderate (9–11) | 1 | 0 | |
| Severe (12–15) | 1 | 0 | |
| Well-Being | |||
| Geriatric Depression Scale (n = 13) | 3.00 | 3.00 | z = −0.36, p = 0.720 |
| Daily Fatigue Form (n = 13) | 3.38 | 3.28 | z = −1.68, p = 0.092 |
| Sleep Quality (n = 12) | 2.00 | 1.00 | z = −0.54, p = 0.589 |
| Lighting Feedback (n = 13) | |||
| Bedroom | 2.00 | 2.00 | z = −0.21, p = 0.833 |
| Kitchen | 2.00 | 2.00 | z = −0.21, p = 0.833 |
| Living Room | 2.00 | 2.00 | z = −1.03, p = 0.302 |
| Bathroom | 2.00 | 2.00 | z = −0.54, p = 0.590 |
Participants’ sleep and rest–activity variables were averaged over the last valid 14 days of study participation in each condition (minimum 10 days). Geriatric depression total scores range from 0 to 15, with scores 5–8 = mild depression; 9–11 = moderate depression; and 12–15 = severe depression. Fatigue scores ranged from 0 (no fatigue) to 5 (high fatigue). Sleep quality scores range from 0 (very good) to 3 (very bad). Lighting responses were scored on a 6-point scale ranging from −3 (extremely dissatisfied) to 3 (extremely satisfied). α = 0.05.