Fig. 2

Representing mechanisms of implementation strategies. We use a diagram (using conventions of a directed acyclic graph) to illustrate the components of a mechanism. In this representation, a Strategy (S) is the implementation actions undertaken to change an implementing outcome. Mediators (M) are all the nodes or steps in a directed pathway from the Strategy to the Outcome (O) passes. Pathways (P) are all unique directed paths from the Strategy to the Outcome. For illustrative purposes, the Strategy (e.g., training) in this diagram acts through three mediators and through three different pathways. Pathway 1 is S-M1-O. Pathway 2 is S-M1-M2-M3-O. Pathway 3 is S-M2-M3-O. Note that M1 is not only a mediator of S through the S-M1-O pathway, but also a moderator of the effect of S-M2-M3-O (by also acting on M2). We consider the “mechanism” as all the mediators and pathways between S and O