Survival analysis in infectious disease research: describing events in time.

Survival analysis methods can be used in infectious disease research to describe the occurrence and timing of clinical or other events subject to censoring and truncation. Here, the survival, hazard, and cumulative hazard functions are defined and simple nonparametric estimators are provided using an illustrative example of survival after AIDS diagnosis. An understanding of these foundational measures is central for an informed use of the survival analysis methods common in infectious disease research.