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Table 3 Effect of the intervention on potential mediators and the associations between changes in mediators and changes in weight at 3- and 9-months (using imputation for missing data)

From: Improved eating behaviours mediate weight gain prevention of young adults: moderation and mediation results of a randomised controlled trial of TXT2BFiT, mHealth program

Hypothesized mediators Month Direct effect of intervention on weight Intervention effect on potential mediators Association between potential mediators and weight change Mediated effect
C’ (SE) P A (SE) P B (SE) P AB (SE) 95 % CI AB/(C’ + AB)
Fruit 3 −1.12 0.34 <0.01 0.21 0.09 0.02 −0.30 0.24 0.24 −0.06 0.07 −0.27, 0.04 3.26 %
  9 −1.38 0.55 0.01     −0.10 0.39 0.82 0.00 0.10 −0.23, 0.19 0.17 %
Vegetables 3 −1.12 0.34 <0.01 0.48 0.12 <0.01 −0.70 0.18 <0.01 −0.34 0.14 −0.70, −0.11 18.48 %
  9 −1.38 0.55 0.01     −0.79 0.28 <0.01 −0.39 0.20 −0.92, −0.08 17.00 %
SSB 3 −1.12 0.34 <0.01 0.27 0.08 <0.01 −0.50 0.27 0.07 −0.14 0.09 −0.34, −0.04 7.61 %
  9 −1.38 0.55 0.01     −0.61 0.26 0.02 −0.29 0.14 −0.64, −0.07 17.37 %
Take-out meals 3 −1.12 0.34 <0.01 0.29 0.07 <0.01 −0.38 0.30 0.20 −0.11 0.10 −0.35, 0.06 5.41 %
  9 −1.38 0.55 0.01     −0.34 0.44 0.44 −0.11 0.13 −0.40, 0.11 4.80 %
PA MET mins 3 −1.12 0.34 <0.01 221.45 201.8 0.27 0.00 0.00 0.20 −0.03 0.06 −0.22, 0.03 1.63 %
  9 −1.38 0.55 0.01     0.00 0.00 0.43 0.04 0.05 −0.02, 0.21 −1.74 %
PA total days 3 −1.12 0.34 <0.01 0.95 0.39 0.02 −0.04 0.06 0.49 −0.04 0.08 −0.24, 0.10 2.17 %
  9 −1.38 0.55 0.01     −0.16 0.1 0.12 −0.16 0.14 −0.53, 0.02 6.97 %
  1. Table design adapted from Hollis et al. (2013) [13]; C’ = unstandardised regression coefficient of the intervention predicting change in weight with mediator in the model. (SE standard error); A = unstandardised regression coefficient of the intervention condition predicting hypothesised mediators; B = unstandardised regression coefficient of the hypothesised mediator predicting weight with intervention condition included in the model; AB = product-of-coefficients estimate. (95 % CI = 95 % confidence interval, Bootstrap bias corrected 95 % confidence intervals of the mediated effect); AB/(C’ + AB) = Proportion of intervention weight effect that was mediated