Adherence
Standard group-based behavioral weight loss programs do not produce clustered weight loss outcomes among members, meaning individual success is not significantly influenced by the performance of other group members.
If you join a standard group weight loss program, your results will likely depend on your own adherence, not how well your classmates do. The group format itself does not guarantee that you will benefit from their success or fail because of their failure. To get social benefits, the program must explicitly use strategies like team competitions or pre-existing social bonds.
Weight losses did not cluster among members of a treatment group (intra-class correlation [ICC] of 0.007)... These findings suggest that it may not be necessary to control for clustering in behavioral weight loss studies, they also indicate that merely treating individuals in groups is not sufficient to harness social influences on weight loss.
Why this rating
Large multicenter RCT (Look AHEAD) with 2329 participants across 209 groups provides robust statistical power.
Source
Do weight loss and adherence cluster within behavioral treatment groups?
Rena R. Wing et al. · Obesity · 2013
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