Mediation Analyses

Editorial on reporting guidelines from Equator network: https://jamanetwork.com/journals/jama/article-abstract/2784377

Definitions:

Difference between confounders and mediators:

• a confounder is associated with the treatment / exposure, is not affected by the treatment, and influences the disease outcome independent of the treatment / exposure.
• similarly, a mediator is related to the treatment / exposure but IS affected by the treatment and influences the outcome.

Action theory: explains why the intervention affects the proposed mediator. In a RCT, the confounders are balanced with respect to describing this relationship.

Conceptual theory: explains how the mediator affects the outcome. In an RCT, the confounders are NOT necessarily balanced with respect to describing this relationship (because mediators are NOT randomized).