Crystal Smit

Chapter 4 84 To examine these significant interactions, we conducted simple slope analysis. Figures 4.3b and 4.3c present the significant interaction, with water consumption at T2 (adjusted for T1) on the y -axis, conditions on the x -axis and separate regression lines for participants with high (+1 SD ) and low (-1 SD ) injunctive norms. Figure 4.3b indicates that there was a positive relation between conditions and water consumption at T2 (adjusted for T1) for low injunctive norms ( b = -.52, SE = .26, p = .044) and a negative relation for high injunctive norms ( b = .37, SE = .29, p = .206). Figure 4.3c also indicates that there was a positive relation between conditions and water consumption at T2 (adjusted for T1) for low injunctive norms ( b = -.54, SE = .28, p = .056) and a negative relation for high injunctive norms (and b = .16, SE = .44, p = .710), but neither slope significantly differed from zero. Thus, these interactions collectively suggest that children reporting lower injunctive norms consumed more water in the social network intervention condition and less water in the active control condition and control condition compared to those with higher norms. Table 4.5 Results for the model testing injunctive norms as a moderator of the mean-level differences between conditions on water consumption ( N = 451) Water consumption b SE β p CI Regression paths Active control [1] vs. SNI [0]—Behavior T2 -.07 .18 - .02 .685 -0.11 – 0.07 Control [1] vs. SNI [0]—Behavior T2 -.19 .33 - .05 .564 -0.21 – 0.11 Injunctive norms T1—Behavior T2 -.18 .09 - .17 .039 -0.33 – 0.01 Active control [1] vs. SNI [0] X Injunctive norms T1—Behavior T2 .26 .12 .14 .050 -0.00 – 0.28 Control [1] vs. SNI [0] X Injunctive norms T1—Behavior T2 .21 .11 .11 .050 0.00 – 0.22 Active control [1] vs. SNI [0]—Behavior T3 -.27 .24 - .07 .267 -0.18 – 0.05 Control [1] vs. SNI [0]—Behavior T3 -.23 .21 - .05 .277 -0.15 – 0.04 Injunctive norms T1—Behavior T3 .06 .04 .05 .122 -0.01 – 0.03 Active control vs. SNI [0] X Injunctive norms T1—Behavior T3 -.13 .09 - .06 .163 -0.15 – 0.03 Control [1] vs. SNI [0] X Injunctive norms T1—Behavior T3 -.13 .08 - .07 .095 -0.14 – 0.01 Stability paths Behavior T1—Behavior T2 .51 .06 .47 <.001 0.36 – 0.58 Behavior T2—Behavior T3 .62 .05 .57 <.001 0.50 – 0.65 Note. b , unstandardized regression coefficient estimating the mean-level difference between conditions, adjusted for previous consumption; SE , standard error; β , standardized regression coefficient; CI = 95% confidence interval; SNI, social network intervention; T1, Time 1; T2, Time 2; T3, Time 3; numbers in parentheses represent the binary dummy coded values; SNI is the reference category in the model.