Fig. 2
From: A scoping review of studies using observational data to optimise dynamic treatment regimens
A dynamic treatment regimen (DTR) causal diagram. Covariates (O1, O2), treatments (A1, A2), and the outcome (Y) are each represented by a node with causal relationships shown as directed edges (arrows). Note that the edges are directional and it not possible for a node to cycle back to itself along the graph’s edges, hence it is a directed acyclic graph