Table 4.
Multilevel Modeling Analyses Predicting Health Behavior after an Intervention and the Cross-Level Interaction between Individual Characteristics and Times
| Baseline | Pre-intervention Change from Baseline | Post-intervention Change from Baseline | ||||||||
| Within-Subject Fixed Effects | Parameter | Coeff. | SE | Parameter | Coeff. | SE | Parameter | Coeff. | SE | |
| Occurrence of exercise | Intercept | γ00 | 1.66 | .15 | γ10 | -.39 | .09 | γ20 | -.30 | .09 |
| Group | γ01 | .07 | .20 | γ11 | .25 | .11 | γ21 | .58* | .11 | |
| Variety of exercises | Intercept | γ00 | .40 | .13 | γ10 | -.25 | .19 | γ20 | -.14 | .19 |
| Group | γ01 | -.07 | .17 | γ11 | .22 | .24 | γ21 | .43* | .24 | |
| - Occurrence of stretching | Intercept | γ00 | .56 | .19 | γ10 | -.27 | .14 | γ20 | -.18 | .14 |
| Group | γ01 | .19 | .24 | γ11 | .11 | .18 | γ21 | .67* | .17 | |
| - Occurrence of walking | Intercept | γ00 | .56 | .22 | γ10 | -.49 | .14 | γ20 | -.72 | .16 |
| Group | γ01 | -.22 | .29 | γ11 | .41 | .19 | γ21 | .76* | .21 | |
| - Occurrence of strengthening exercises | Intercept | γ00 | -.48 | .29 | γ10 | -.42 | .19 | γ20 | .05 | .18 |
| Group | γ01 | .60 | .37 | γ11 | .20 | .24 | γ21 | .14 | .22 | |
| - Occurrence of relaxation activities | Intercept | γ00 | 1.17 | .26 | γ10 | -.15 | .09 | γ20 | -.20 | .09 |
| Group | γ01 | -.89 | .35 | γ11 | .54 | .13 | γ21 | .79* | .13 | |
| Variety of relaxation activities | Intercept | γ00 | .07 | .18 | γ10 | -.17 | .19 | γ20 | -.09 | .20 |
| Group | γ01 | -.69 | .26 | γ11 | .60 | .29 | γ21 | .60 | .22 | |
| Occurrence of leisure activities | Intercept | γ00 | 1.67 | .12 | γ10 | .35 | .08 | γ20 | .23 | .09 |
| Group | γ01 | .09 | .15 | γ11 | -.34 | .11 | γ21 | -.29 | .12 | |
| Variety of leisure activities | Intercept | γ00 | .17 | .14 | γ10 | .37 | .18 | γ20 | .29 | .19 |
| Group | γ01 | .05 | .18 | γ11 | -.27 | .24 | γ21 | -.07* | .25 | |
| Variety of everyday coping behaviors | Intercept | γ00 | 2.14 | .06 | γ10 | -.00 | .07 | γ20 | .09 | .07 |
| Group | γ01 | -.02 | .07 | γ11 | .05 | .09 | γ21 | .02 | .09 | |
| Social networks | Intercept | γ00 | 6.48 | .28 | γ10 | -.46 | .18 | γ20 | -.09 | .19 |
| Group | γ01 | -.16 | .37 | γ11 | .25 | .24 | γ21 | .29 | .26 | |
* p < .05
Significance of coefficient γ21 is indicative of intervention effects using the following model:
Level 1 model: Outcome = β0j + β1jX1 + β2jX2+ rij
Level 2 model: T1 β0j = γ00 + γ01 Grj + uoj
T2 β1j = γ10 + γ11 Grj
T3 β2j = γ20 + γ21 Grj
Meaning of Coefficients:
γ00 = Predicted value in outcome variable at baseline for participants in control group
γ01 Grj = Predicted difference in outcome variable at baseline for participants in experimental group
γ10 = Predicted change in outcome variable from baseline to pre-intervention for participants in control group
γ11 Grj = Predicted difference in change in outcome variable from baseline to pre-intervention for participants in experimental group
γ20 = Predicted change in outcome variable from baseline to post-intervention for participants in control
γ21 Grj = Predicted difference in change in outcome variable from baseline to post-intervention for participants in experimental group.
where i: 1 .....N individuals ; rij: level 1 error term ; γ : parameter coefficients ; uoj: level-2 random effect ; β: coefficient; Gr: group membership (1 = experimental, 0 = control) ; X1: dummy variable (1 = pre-intervention, 0 = otherwise) ; X2: dummy variable(1 = post-intervention, 0 = otherwise)