Supplementary Fig. 1.

Directed Acyclic Graph illustrating causal assumptions applied to potential confounding and mediating variables in a cohort of patients with cervical cancer where the exposure of interest is HIV serostatus and the outcome of interest is overall survival. Arrows represent direction of causal effects between two variables. The black pathway represents the hypothesized association between HIV and survival; the red pathway represents a potential confounding relationship; green pathways represent potential mediating relationships.