Table 2.
Results from mediation and reciprocal effects analyses (N = 36)
| Predictor | Mediator | Outcome | Model R 2 | Path a | Path b | Path c | Path c′ | Indirect effect |
|---|---|---|---|---|---|---|---|---|
| β (SE) | β (SE) | β (SE) | β (SE) | β (SE) | ||||
| p | p | p | p | p | [95% CI] | |||
| Changes from month 6 to month 12 | ||||||||
| Model 1a | ||||||||
| ΔNegative mood | ΔEmotional eating | ΔFruit/vegetable | .17 | −.15 (.06) | .07 (.04) | −.02 (.01) | −.01 (.01) | −.01 (.01) |
| .047 | .006 | .038 | .042 | .183 | −.03, .00 | |||
| Model 1b | ||||||||
| ΔNegative mood | ΔEmotional eating | ΔSweets | .00 | −.15 (.06) | .01 (.02) | .00 (.01) | .00 (.01) | .00 (.01) |
| .968 | .006 | .419 | .439 | .412 | −.01, .01 | |||
| Model 2a | ||||||||
| ΔSelf-regulation-eating | ΔSelf-efficacy-eating | ΔFruit/vegetable | .20 | −.06 (.71) | −.02 (.01) | −.11 (.05) | −.12 (.05) | .00 (.03) |
| .023 | .466 | .032 | .021 | .016 | −.04, .04 | |||
| Model 2b | ||||||||
| ΔSelf-regulation-eating | ΔSelf-efficacy-eating | ΔSweets | .09 | −.06 (.71) | .00 (.01) | −.05 (.03) | −.05 (.03) | .00 (.01) |
| .223 | .466 | .448 | .041 | .043 | −.01, .01 | |||
| Model 3 | ||||||||
| ΔSelf-regulation-exercise | ΔExercise self-efficacy | ΔPhysical activity | .23 | .78 (.26) | .35 (.22) | .93 (.35) | .65 (.38) | .27 (.18) |
| .007 | .003 | .061 | .006 | .050 | .04, .67 | |||
| Model 3 (reciprocal analysis) | ||||||||
| ΔSelf-regulation-exercise | ΔPhysical activity | ΔExercise self-efficacy | .23 | .26 (.09) | .65 (.38) | .52 (.20) | .35 (.22) | .17 (.11) |
| .014 | .003 | .050 | .008 | .061 | .02, .41 | |||
| Changes from month 6 to month 24 | ||||||||
| Model 4a | ||||||||
| ΔNegative mood | ΔEmotional eating | ΔFruit/vegetable | .12 | .24 (.12) | −.07 (.04) | −.05 (.03) | −.03 (.03) | −.02 (.02) |
| .050 | .025 | .040 | .044 | .135 | −.06, .01 | |||
| Model 4b | ||||||||
| ΔNegative mood | ΔEmotional eating | ΔSweets | .30 | .24 (.12) | .06 (.02) | .03 (.01) | .01 (.01) | .01 (.01) |
| .003 | .025 | .002 | .032 | .161 | .01, .03 | |||
| Model 4b (reciprocal analysis) | ||||||||
| ΔNegative mood | ΔSweets | ΔEmotional eating | .31 | .03 (.01) | 3.80 (1.22) | .24 (.12) | .13 (.11) | .11 (.08) |
| .002 | .032 | .002 | .025 | .122 | .03, .30 | |||
| Model 5a | ||||||||
| ΔSelf-regulation-eating | ΔSelf-efficacy-eating | ΔFruit/vegetable | .24 | 2.63 (.75) | .02 (.01) | .15 (.06) | .09 (.07) | .06 (.04) |
| .010 | .001 | .040 | .006 | .084 | .01, .15 | |||
| Model 5a (reciprocal analysis) | ||||||||
| ΔSelf-regulation-eating | ΔFruit/vegetable | ΔSelf-efficacy-eating | .33 | .15 (.06) | 3.88 (2.15) | 2.63 (.75) | 2.03 (.80) | .59 (.41) |
| .001 | .006 | .040 | .001 | .084 | .01, 1.35 | |||
| Model 5b | ||||||||
| ΔSelf-regulation-eating | ΔSelf-efficacy-eating | ΔSweets | .32 | 2.63 (.75) | −.004 (.01) | −.11 (.03) | −.10 (.03) | −.01 (.01) |
| .001 | .001 | .295 | <.001 | .002 | −.05, .01 | |||
| Model 6 | ||||||||
| ΔSelf-regulation-exercise | ΔExercise self-efficacy | ΔPhysical activity | .52 | 1.66 (.28) | .64 (.27) | 2.36 (.46) | 1.30 (.62) | 1.06 (.52) |
| <.001 | <.001 | .012 | <.001 | .022 | .30, 1.99 | |||
| Model 6 (reciprocal analysis) | ||||||||
| ΔSelf-regulation-exercise | ΔPhysical activity | ΔExercise self-efficacy | .58 | 2.36 (.46) | .23 (.10) | 1.66 (.28) | 1.11 (.35) | .54 (.24) |
| <.001 | <.001 | .012 | <.001 | .001 | .19, .99 | |||
| Changes from month 12 to month 24 | ||||||||
| Model 7a | ||||||||
| ΔNegative mood | ΔEmotional eating | ΔFruit/vegetable | .52 | −.12 (.06) | −.04 (.03) | .06 (.01) | .05 (.01) | .01 (.01) |
| <.001 | .022 | .065 | <.001 | <.001 | .00, .02 | |||
| Model 7b | ||||||||
| ΔNegative mood | ΔEmotional eating | ΔSweets | .18 | −.12 (.06) | .03 (.02) | −.01 (.01) | −.01 (.01) | .00 (.00) |
| .039 | .022 | .057 | .022 | .077 | −.01, .00 | |||
| Model 8a | ||||||||
| ΔSelf-regulation-eating | ΔSelf-efficacy-eating | ΔFruit/vegetable | .50 | 1.98 (.72) | .06 (.01) | .08 (.06) | −.04 (.05) | .12 (.06) |
| <.001 | .005 | <.001 | .110 | .216 | .05, .24 | |||
| Model 8a (reciprocal analysis) | ||||||||
| ΔSelf-regulation-eating | ΔFruit/vegetable | ΔSelf-efficacy-eating | .57 | .08 (.06) | 7.80 (1.43) | 1.98 (.72) | 1.36 (.54) | .62 (.54) |
| <.001 | .110 | <.001 | .005 | .008 | −.19, 1.58 | |||
| Model 8b | ||||||||
| ΔSelf-regulation-eating | ΔSelf-efficacy-eating | ΔSweets | .27 | 1.98 (.72) | −.01 (.01) | −.09 (.03) | −.08 (.03) | −.01 (.01) |
| .005 | .005 | .189 | <.001 | .005 | −.03, .01 | |||
| Model 9 | ||||||||
| ΔSelf-regulation-exercise | ΔExercise self-efficacy | ΔPhysical activity | .49 | 1.13 (.21) | .92 (.31) | 1.81 (.42) | .78 (.51) | 1.04 (.51) |
| <.001 | <.001 | .003 | <.001 | .070 | .32, 2.00 | |||
| Model 9 (reciprocal analysis) | ||||||||
| ΔSelf-regulation-exercise | ΔPhysical activity | ΔExercise self-efficacy | .57 | 1.81 (.42) | .23 (.08) | 1.13 (.21) | .71 (.24) | .42 (.22) |
| <.001 | <.001 | .003 | <.001 | .003 | .12, .87 | |||
Analyses were based on a bootstrapping method for mediation incorporating 20,000 resamples (Preacher and Hayes 2008). A reciprocal analysis was conducted when mediation within the initial model was significant
Path a predictor → mediator, Path b mediator → outcome, Path c = predictor → outcome, Path c′ = predictor → outcome, after controlling for the mediator, 95% CI 95% confidence interval, one-tailed test