Fig. 1.

A simplified directed acyclic graph of the potential relationships between sociodemographic factors and acute kidney injury. Primary exposures: race, health insurance status (insurance), household urbanization, gender, and age. Primary outcome: acute kidney injury (AKI). Confounders are variables that have an arrow going towards exposure and towards outcome (directly or indirectly). Examples would be genetic history between Race and AKI (indirectly via comorbidities). Mediators are variables along the causal pathway (arrow coming from exposure and then arrow going towards outcome). Example would be Hospital characteristics as a mediator between Insurance and AKI. Mediators are variables not typically controlled for in multivariate modeling as they can then introduce bias