Table 7.
Test of Hypothesized Mediators of the Memory Support Intervention
| Fixed effects
|
Random effects
|
||||
|---|---|---|---|---|---|
| Criteria | Beta | SE | p |
Level 2: between- subject variance |
Level 1: within- subject variance |
| 1. Effect of the treatment on the outcome (Path c) | |||||
| CT+MS vs. CT-as-usual --> Δ IDS-SR | −0.17 | 0.23 | 0.46 | 0.18 | 0.30 |
| CT+MS vs. CT-as-usual --> Δ GAF | 0.48 | 0.25 | 0.05 | 0.11 | 0.33 |
| 2. Effect of the treatment on the mediator (Path a) | |||||
| CT+MS vs. CT-as-usual --> Δ Cumulative recall | 0.29 | 0.22 | 0.20 | 0.66 | 0.23 |
| CT+MS vs. CT-as-usual --> Δ Past session recall | 0.57 | 0.38 | 0.14 | 0.26 | 0.71 |
| 3. Relation between change in mediator and outcome (Path b) | |||||
| Δ Cumulative recall --> Δ IDS-SR | −0.14 | 0.14 | 0.29 | 0.17 | 0.30 |
| Δ Past session recall --> Δ IDS-SR | −0.22 | 0.15 | 0.14 | 0.16 | 0.30 |
| Δ Cumulative recall --> Δ GAF | −0.05 | 0.15 | 0.74 | 0.10 | 0.38 |
| Δ Past session recall --> Δ GAF | −0.21 | 0.17 | 0.21 | 0.14 | 0.34 |
| 4a. Effect of treatment on outcome with control for change inmediator (Path c) | |||||
| CT+MS --> Δ IDS-SR | Cumulative recall | −0.11 | 0.25 | 0.66 | 0.16 | 0.29 |
| CT+MS --> Δ IDS-SR | Past session recall | −0.13 | 0.25 | 0.60 | 0.15 | 0.30 |
| CT+MS --> Δ GAF | Cumulative recall | 0.54 | 0.27 | 0.05 | 0.11 | 0.34 |
| CT+MS --> Δ GAF | Past session recall | 0.52 | 0.26 | 0.04 | 0.15 | 0.30 |
| t | Δ b (%) | ||||
| 4b. Effect of treatment on outcome, with control for change in mediator (Path c’), significantly reduced or eliminated compared with effect of the treatment on the outcome (Path c) | |||||
| CT+MS --> Δ IDS-SR | Cumulative recall | −1.54 | 35% | |||
| CT+MS --> Δ IDS-SR | Past session recall | −0.97 | 24% | |||
| CT+MS --> Δ GAF | Cumulative recall | −1.14 | −11% | |||
| CT+MS --> Δ GAF | Past session recall | −0.72 | −7% | |||
Note. Beta = standardized regression coefficient. t < −2.01 indicates statistical significance at two-tailed α = 0.05. | indicates controlling for. Note that we omitted Criteria 5 of Stice et al., 2007 because no IDS-SR was available at session 7 and Criteria 1–4 are more typically conducted in the literature. Freedman & Schatzkin’s (1992) method was used to calculate t-statistic. Paths a, b, c, and c’ are indicated in the diagrams in the Supplemental Material.