Main analysis
weight loss
REGRESSION
The hypothesized model tested predicted 23.5% of weight change variance (Path analysis: Estimates of the regression coefficients. Note: Only significant and direct paths are shownDecreases in weight were predicted by improvements in needs satisfaction (β = -0.140), action plans (β  = -0.122), coping plans (β  = -0.095) and action control (β  = -0.294), and by increases in exercise controlled motivations (β  = 0.091). Note that due to how the variable’s changes were calculated, one should, for example, read that the negative value of the estimate for action control represents that improvements in action control were associated with more weight loss, a positive outcome.An increase in action plans was predicted by improvements in climate care (β  = 0.139), goal content intrinsic (β  = 0.067), and needs satisfaction (β  = 0.230). Increases in coping plans were predicted by improvements in climate care (β  = 0.158), and needs satisfaction (β  = 0.233). An increase in action control was predicted by improvements in climate care (β  = 0.083), goal content intrinsic (β  = 0.101), and needs satisfaction (β  = 0.132). And finally, a decrease in exercise controlled motivation was predicted by improvements in psychological needs satisfaction (β  = -0.114), and by increases in goal content extrinsic (β  = 0.231).For a complete table of the direct associations, please refer to the Supplementary file Table Testing the logic model: standardized parameter estimates of indirect effects predicting weight changeOnly significant indirect effects are shown. Negative coefficients represent more weight loss. Exercise Controlled Mot.—Exercise Controlled MotivationSummary of the significant paths in the primary analysisThe italics represent the weight regain indirect effect processesOther results in Table Improvements in intrinsic goal contents were associated with better weight loss management. The indirect effects showed that positive changes in intrinsic goal contents improved weight change outcomes via increases in action control (β = -0.030, 95% BcCI = -0.049; -0.013), action plans (β = -0.008, 95% BcCI = -0.019; -0.002), and decreases in exercise controlled motivation (β = 0.004, 95% BcCI = 0.000; 0.011).As expected, the results regarding the extrinsic goal contents were opposite to the previous results. Specifically, an increase in the extrinsic goal contents was associated with worse weight management outcomes via decreases in action control (β = 0.017, 95% BcCI = 0.001; 0.034), coping plans (β  = 0.006, 95% BcCI = 0.001; 0.016), action plans (β = 0.009, 95% BcCI = 0.002; 0.020), and exercise controlled motivation (β = 0.021, 95% BcCI = 0.009; 0.035).Overall, higher scores of climate care and positive changes in needs satisfaction, intrinsic goal contents, action control, coping plans, action plans, and exercise controlled motivation represented paths for weight regain prevention. As predicted in the logic model, improvements in these variables positively affected weight regain prevention. However, although the logic model predicted that increases in exercise controlled motivation would lead to poorer weight regain management, the results showed that increases in this variable were also associated with better weight loss management.In the initial analysis, we focused on a specific research question outlined in NoHoW's publication plan. However, we conducted additional analyses where the timeframes of variables did not overlap. For instance, motivational variables were examined within a timeframe of 0–6 months, while self-regulation variables were examined within a timeframe of 6–12 months. The results of these analyses showed that the model had low levels of data fit. This suggests that the expected temporal dissociation, as predicted by some theoretical models, was not observed in our trial. It is possible that some variables' changes may be intertwined rather than occurring as distinct, stage-like processes or that these psychosocial processes may represent independent paths.