Table 2.
Mixed effects regression results indicating the impact of the PP intervention (compared to CC) on psychological outcomes at 4 and 8 weeks.*
| Outcome | 4 weeks | 8 weeks | ||||||
|---|---|---|---|---|---|---|---|---|
| Coefficient | 95% CI | Effect size** | p | Coefficient | 95% CI | Effect size** | p | |
| Positive Affect (PANAS) | 6.81 | −1.22 to 14.83 | 1.16 | .10 | 5.58 | −1.55 to 12.71 | 0.95 | .13 |
| Gratitude (GQ-6) | 3.91 | −3.82 to 11.64 | 0.68 | .32 | 2.99 | −3.95 to 9.93 | 0.52 | .40 |
| Optimism (LOT-R) | 5.61 | −0.59 to 11.81 | 1.24 | .08 | 4.96 | −0.54 to 10.46 | 1.10 | .08 |
| Depression (QIDS-SR) | −0.05 | −6.38 to 6.27 | −0.01 | .99 | −0.31 | −5.95 to 5.32 | −0.07 | .91 |
| Hopelessness (BHS) | −3.67 | −9.81 to 2.47 | −0.81 | .24 | −1.10 | −6.56 to 4.36 | −0.24 | .69 |
| Suicidality (CHRT) | 4.69 | −4.67 to 14.05 | 0.68 | .33 | 2.87 | −5.44 to 11.18 | 0.42 | .50 |
*
Results of mixed effects regression models. Coefficients are Group x Time interaction values.
**
Effect size was calculated by dividing the Group x Time interaction coefficient of each variable at each time point by the standard deviation (SD) of the residual in the regression model.
BHS = Beck Hopelessness Scale; CHRT = Concise Health Risk Tracking; GQ-6 = Gratitude Questionnaire-6; LOT-R = Life Orientation Test – Revised; PANAS = Positive and Negative Affect Schedule; QIDS-SR = Quick Inventory of Depressive Symptomatology – Self-Report