Examining the influence of a text message-based sleep and physical activity intervention among young adult smokers in the United States

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)	1.039 (−0.095, 2.172)	0.07	1.373 (0.262, 2.484)*	0.02**
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)	0.175 (−1.464, 1.815)	0.83	−0.332 (−2.135, 1.470)	0.71
Sleep quality score^c
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)	−1.468 (−4.570, 1.633)	0.34	−1.620 (−4.821, 1.581)	0.31

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

ISSN: 1471-2458