Event History and Survival Data
This chapter discusses the use of special techniques that constitute survival and event history analysis. It describes the concepts of right censoring and left truncation. What characterizes event history and survival data the most is its dynamic nature. Survival data constitute the simplest form of event history data. The data set oldmort in eha contains survival data from the parish Sundsvall in the mid-east of 19th century Sweden. The name oldmort is an acronym for old age mortality. The modern theory of survival analysis offers simple ways to deal with right-censored data. There are three basic elements which must be well defined: a time origin, a scale for measuring time, and an event. The ultimate study object in survival analysis is the time it takes from entering state Alive until entering state dead. In a clinical trial for treatment of cancer, starting event time may be time of operation, and the final event time is time of relapse.