Directed Acyclic Graphs to Identify Confounders: A Case Study Exploring the Impact of Hunger on Virologic Suppression Among HIV-Positive Illicit Drug Users Receiving HIV Treatment A Anema, ME Karim, MJ Milloy, E Wood, LC McCandless January 2015 Source Document DAG causal-inference Related Marginal structural Cox models for estimating the association between beta-interferon exposure and disease progression in a multiple sclerosis cohort Can joint replacement reduce cardiovascular risk?