Survival Data

Preliminaries

The most immediate examples of survival data come from demography and actuarial science and concern the duration of human life. The issues of statistical analysis that arise are similar to those in many fields. Thus survival time may be the length of time before a piece of industrial equipment fails, the length of time before a firm becomes bankrupt, the duration of a period of employment or, particularly in a medical or epidemiological context, the time between diagnosis of a specific condition and death from that condition.

Depending on the perspective involved the term failure time may be used instead of survival time.

Central requirements are that for each study individual we have a clear time origin and a clear end point. For example, time may be measured from the instant an individual enters the study population and the end point may be death from a specific cause, or death (all causes) or cure. Normally the passage of time is clearly defined in the natural way....