Table 1.
Descriptive statistics for the study variables.
| Variable | Mean (SD) or n (%) | Range |
|---|---|---|
| Age | 71.6 (6.6) | 55–83 |
| Gender, female | 51 (67%) | n/a |
| Education, >HS diploma | 62 (82%) | n/a |
| Employment, retired | 70 (92%) | n/a |
| MMSE | 28.8 (1.2) | 25–30 |
| MoCA | 24.7 (2.6) | 17–29 |
| MW-days of wear | 15.2 (2.7) | 6–29 |
| MW-latency (mins) | 5.4 (4.8) | 0–23 |
| MW-efficiency | 82.7 (5.8) | 65.4–95.2 |
| MW-duration (mins) | 408.8 (46.4) | 293–508 |
| MW-fragmentation | 31.7 (11.3) | 12–73 |
| MW-composite (z-score) | 0.01 (0.85) | −2.84 to 1.72 |
| L5 Start (hr:min) | 0:40 (1:01) | 23:00–3:00 |
| M10 Start (hr:min) | 8:19 (1:14) | 5:00–12:00 |
| Relative amplitude | 0.89 (0.05) | 0.75–0.98 |
| Inter-daily stability | 0.54 (0.11) | 0.31–0.84 |
| Intra-daily variability | 0.87 (0.20) | 0.47–1.47 |
| PSQI-latency (mins) | 13.5 (11.0) | 2–45 |
| PSQI-efficiency | 79.6 (14.4) | 44.4–100.0 |
| PSQI-duration (mins) | 376.7 (79.2) | 180–570 |
| PSQI-disturbances | 10.3 (3.4) | 1–17 |
| PSQI-sleep quality | 1.2 (0.9) | 0–3 |
| PSQI-total | 7.4 (4.1) | 1–18 |
| PSQI sleep quality category, “good” | 28 (36%) | n/a |
| SD-latency | 22.6 (16.2) | 2–72.9 |
| SD-accuracy | 91.2 (12.9) | 35.7–100.0 |
| SD-awakenings | 2.1 (1.0) | 0.6–5.8 |
| SD-quality | 3.4 (0.7) | 2–5 |
| SD-sleep window (mins) | 461.7 (50.2) | 364.3–617.5 |
| SD-sleep duration (mins) | 398.0 (61.7) | 163.7–535.8 |
HS, high school; MMSE, Mini-Mental State Examination; MoCA, Montreal Cognitive Assessment; MW, motion watch; PSQI, Pittsburgh Sleep Quality Index; SD, sleep diary.