Table 3. Actor-partner interdependence model (APIM) of perceived distress-social support interaction (buffering effect) regressed on health-related quality of life.
| Variable | Two-Intercept Model without covariates | Two-Intercept Model with covariates | ||||
|---|---|---|---|---|---|---|
| Partner With Dementia a | Caregiving Partner a | Contrast test for differences of coefficients across care roles | Partner With Dementia a | Caregiving Partner a | Contrast test for differences of coefficients across care roles | |
| β (SE) | β (SE) | β (SE) | β (SE) | β (SE) | β (SE) | |
| Intercept | -.04 (.08) | .39 (.08)*** | .43 (.11)*** | -.40 (.17)* | .28 (.17)** | .67 (.23)** |
| Time | -.21 (.08)* | -.29 (0.8)*** | -.09 (.11) | -.13 (.08) | -.27 (.08)** | -.14 (.11) |
| Actor-Effects (time varying) | ||||||
| Actor perceived distress | -.37 (.06)*** | -.64 (.07)*** | -.26 (.09)** | -.31 (.06)*** | -.63 (.06)*** | -.32 (.09)*** |
| Actor perceived social support | .15 (.09)* | .17 (.06)* | .02 (.11) | .21 (.08)** | .17 (.05)** | -.04 (.10) |
| Actor distress*actor support interaction | .15 (.07)* | .13 (.06)* | -.02 (.09) | .14 (.06)* | .13 (.06)* | -.02 (.09) |
| Partner-Effects (time varying) | ||||||
| Partner perceived distress | .04 (.07) | .04 (.06) | .01 (.10) | .04 (.07) | .02 (.06) | -.01 (.09) |
| Partner perceived social support | .03 (.06) | -.03 (.07) | -.02 (.11) | .01 (.06) | -.05 (.08) | -.06 (.11) |
| Partner distress*partner support interaction | .03 (.06) | .11 (.07) | .00 (.06) | .12 (.07) | .11 (.09) | |
| Actor-Partner-Interaction Effect (time varying) | ||||||
| Actor distress*partner support interaction | -.06 (.05) | .09 (.08) | .15 (.09) | -.04 (.05) | .08 (.08) | .12 (.09) |
| Partner distress*actor support interaction | .09 (.08) | .06 (.05) | -.03 (.10) | .01 (.08) | .05 (.05) | .04 (.09) |
| Covariates | ||||||
| Depressive symptoms (time varying) | -.26 (.06)*** | .04 (.07) | .29 (.09)*** | |||
| Age | .05 (.07) | .02 (.07) | -.03 (.10) | |||
| Gender b | .07 (.13) | .18 (.15) | .11 (.20) | |||
| Functional disability of the patient regressed on both partners quality of life | .20 (.07)** | .08 (.07) | -.12 (.09) | |||
| Cognitive functioning of the patient regressed on both partners quality of life | -.02 (.07) | .01 (.07) | .03 (.10) | |||
| Condition | .22 (.13) | .00 (.13) | -.22 (.18) | |||
| Region | .36 (.15)* | .06 (.15) | -.30 (.21) | |||
| Estimate of variance by care role | .42 (.09)*** | .33 (.07)*** | .25 (.06)*** | .32 (.07)*** | ||
| Correlation between variances of care roles (CHS rho) | .25 (.14) | .14 (.16) | ||||
| Time variance | .04 (.08) | .02 (.07) | ||||
| Residual variance | .23 (.04)*** | .24 (.05)*** | ||||
| -2 Restricted Log Likelihood | 863.68 | 847.91 | ||||
| AIC c | 873.68 | 857.91 | ||||
Note. All continuous variables were grand-mean centered prior to analyses (z-standardization with mean = 0 SD = 1) and can be interpreted like standardized β coefficients.
a Role of care was effect coded -1 = Partner with dementia 1 = Caregiving partner. Functional disability was assessed in partners with dementia via activities of daily living (ADL) scale. Cognitive functioning (memory, attention, and language) was assessed in partners with dementia via Mini-Mental Status Examination (MMSE).
b Gender is coded 0 = Men 1 = Women. Region is coded 0 = suburban or rural 1 = urban. Condition is coded 0 = control 1 = psychosocial group.
c AIC = Akaike’s Information Criterion; in nested models lower AIC values indicate better fit. CHS rho = test of non-independence across partners.
*p < .05;
** p < .01;
***p < .001