Theory 74/Field programme/Nutrition trials
Adherence Mediates
The claim
Most of the variance in diet trial outcomes is explained by adherence rather than by assignment, so intention-to-treat analyses understate effects.
01Mechanism
Biological effect requires sustained exposure; non-adherent participants dilute it.
02Prediction
Effect size should scale with adherence.
03Refutation
Effect independent of adherence would remove the mediation.