Table 2.
Means, standard deviations, within effects, and interaction effects of group (IG vs. TAUG) × time (T1 vs. T2)
| Variable | Mean values and standard deviations | Within effect (t1 vs t2; ANOVA) |
Group × time interaction (2 × 2 ANOVA) |
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| M(t1) | SD(t1) | M(t2) | SD(t2) | F | df | p | ηp2 | F | df | p | ηp2 | |||
| Self-efficacy | TAUG | 2.81 | .43 | 2.79 | .45 | 3.80 | 1.53 | .06 | - | 5.86 | 1.53 | .02 | .10 | |
| IG | 2.75 | .49 | 2.95 | .33 | ||||||||||
| Psychiatric symptoms | TAUG | .91 | .74 | .91 | .80 | .31 | 1.52 | .58 | - | 1.83 | 1.52 | .67 | - | |
| IG | .82 | .60 | .76 | .63 | ||||||||||
| Craving | TAUG | 1.53 | .73 | 1.30 | .54 | 22.16 | 1.54 | .00 | .29 | 1.88 | 1.54 | .18 | - | |
| IG | 1.29 | .60 | .88 | .53 | ||||||||||
| Tobacco dependence | TAUG | 6.20 | 1.76 | 6.00 | 1.73 | 3.67 | 1.54 | .06 | - | .96 | 1.54 | .33 | - | |
| IG | 5.53 | 2.03 | 4.91 | 2.31 | ||||||||||
| HRV (RMSSD) | TAUG | 3.09 | .74 | 3.24 | .73 | 1.48 | 1.47 | .23 | - | .51 | 1.47 | .48 | - | |
| IG | 3.23 | .62 | 3.23 | .60 | ||||||||||
| Frequencies and percentage |
Group × time interaction (GEE) |
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| Category | n(t1) | %(t1) | n(t2) | %(t2) | Wald-χ2 | df | p | B | ||||||
| Smoked cigarettes per day | TAUG |
< 10 11–20 21–30 > 31 |
0 14 8 3 |
0% 56% 32% 12% |
0 13 11 1 |
0% 52% 44% 4% |
4.72 | 1 | .03 | 1.16 | ||||
| IG |
< 10 11–20 21–30 > 31 |
3 13 12 3 |
10% 42% 39% 10% |
8 15 5 3 |
26% 48% 16% 10% |
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TAUG treatment as usual group, IG intervention group, HRV heart rate variability, RMSSD root mean square of successive differences, RMSSD was logistically transformed, GEE generalized estimating equations, p < .05