An introduction to directed acyclic graphs in trauma research.

DAGs can help trauma researchers to understand when they can and when they cannot draw causal conclusions based on research data. This introduction to DAGs should help readers understand their use in the articles on marginal structural models, causal mediation analysis, and instrumental variable methods in this special section, Causal inference and agent-based modeling in trauma research. (PsycInfo Database Record (c) 2023 APA, all rights reserved).