Table 2.
Preintervention and postintervention means, results of the per-protocol (PP) repeated-measure ANOVA analysis, and between-group effect sizes (Cohen d) of primary and secondary outcomes (n=98).
| Measure | Preintervention, mean (SD) | Postintervention, mean (SD) | Between-group effect sizes (intervention group vs waitlist control group after the intervention) | |||||
|
|
|
|
Cohen da (95% CIb) | Partial η2 | ANOVA | |||
|
|
|
|
|
|
F test (df) | P value | ||
| Primary outcome | ||||||||
|
|
Perceived stress (PSS-10c) | |||||||
|
|
|
Intervention (n=42) | 28.41 (5.53) | 24.24 (5.93) | −0.60 (−1.01 to −0.19) | 0.10 | 10.69 (1, 96) | .001 |
|
|
|
Control (n=56) | 28.36 (4.93) | 27.61 (5.38) | —d | — | — | — |
| Secondary outcomes | ||||||||
|
|
Depression (PHQ-9e) | |||||||
|
|
|
Intervention (n=42) | 7.90 (4.24) | 5.95 (3.45) | −0.50 (−0.91 to −0.10) | 0.09 | 9.29 (1, 96) | .003 |
|
|
|
Control (n=56) | 7.86 (4.13) | 7.86 (4.02) | — | — | — | — |
|
|
Anxiety (GAD-7f) | |||||||
|
|
|
Intervention (n=42) | 6.52 (3.69) | 5.62 (3.22) | −0.29 (−0.69 to 0.11) | 0.03 | 3.18 (1, 96) | .08 |
|
|
|
Control (n=56) | 6.41 (3.32) | 6.59 (3.47) | — | — | — | — |
|
|
Somatic symptoms (PHQ-15g) | |||||||
|
|
|
Intervention (n=42) | 9.19 (4.81) | 7.50 (3.78) | −0.36 (−0.76 to −0.04) | 0.07 | 6.92 (1, 96) | .01 |
|
|
|
Control (n=56) | 9.07 (3.89) | 9.00 (4.43) | — | — | — | — |
|
|
Active coping (HAPAh) | |||||||
|
|
|
Intervention (n=42) | 2.21 (0.87) | 2.67 (0.75) | 0.13 (−0.27 to 0.53) | 0.04 | 3.60 (1, 96) | .06 |
|
|
|
Control (n=56) | 2.45 (0.81) | 2.57 (0.78) | — | — | — | — |
aCohen d values based on means and the pooled SD of the PP analysis.
b95% CI of Cohen d (between groups, after the intervention).
cPSS-10: Perceived Stress Scale-10.
dNot applicable.
ePHQ-9: Patient Health Questionnaire-9.
fGAD-7: Generalized Anxiety Disorder-7.
gPHQ-15: Patient Health Questionnaire-15.
hHAPA: health action process approach.