Table 3.
Relative difference in sleep indicators between groups at 3-month follow-up for short sleepers (<6 hours/night)
| Sleep measure | Baseline mean (SD) | 12-week follow-up mean (SD) | Unadjusted difference β (95 % CI)a | P-value | Adjusted difference β (95 % CI)b | P-value |
|---|---|---|---|---|---|---|
| Sleep quantity on work/school nights (hours/night) | ||||||
| Sleep/activity group | 4.27 (0.70) | 5.87 (2.00) | 1.039 (−0.095, 2.172) | 0.07 | 1.373 (0.262, 2.484)* | 0.02** |
| Smoking cessation group | 4.53 (0.84) | 5.05 (1.43) | ||||
| Sleep quantity on non-work/non-school nights (hours/night) | ||||||
| Sleep/activity group | 5.87 (2.23) | 6.93 (2.02) | 0.175 (−1.464, 1.815) | 0.83 | −0.332 (−2.135, 1.470) | 0.71 |
| Smoking cessation group | 7.74 (2.54) | 7.16 (2.32) | ||||
| Sleep quality scorec | ||||||
| Sleep/activity group | 19.33 (4.72) | 17.33 (5.25) | −1.468 (−4.570, 1.633) | 0.34 | −1.620 (−4.821, 1.581) | 0.31 |
| Smoking cessation group | 18.89 (5.13) | 18.58 (4.81) | ||||
SD Standard deviation, CI Confidence interval
n = 34
aAdjusted for baseline sleep
bAdjusted for baseline sleep, change in physical activity, smoking status at follow-up, daily text messaging usage, sex, educational attainment, and race
cSleep quality was assessed using 8 self-report items adapted from the PSQI; scores were the sum of participants' quantified responses for each item, with higher scores being indicative of poorer sleep quality (possible scores ranged from 8 to 32)
*95 % CI does not contain 0
**Significant at p < 0.05