Contents
What is survival analysis epidemiology?
Survival analysis is concerned with the time elapsed from a known origin to either an event or a censoring point. It may deal with survival, such as the time from diagnosis of a disease to death, but can refer to any time dependent phenomenon, such as time in hospital or time until a disease recurs.
What is truncation in survival analysis?
Survival analysis is crucial when observed data are censored or truncated. Truncation occurs when we do not observe individuals with event times that are smaller or larger than certain values.
Are there any statistical models for survival analysis?
There are certain aspects of survival analysis data, such as censoring and non-normality, that generate great difficulty when trying to analyze the data using traditional statistical models such as multiple linear regression.
How are engineering sciences involved in survival analysis?
The engineering sciences have also contributed to the development of survival analysis which is called “reliability analysis” or “failure time analysis” in this field since the main focus is in modeling the time it takes for machines or electronic components to break down.
When is an observation is right censored in survival analysis?
When an observation is right censored it means that the information is incomplete because the subject did not have an event during the time that the subject was part of the study. The point of survival analysis is to follow subjects over time and observe at which point in time they experience the event of interest.
How is the survival function derived from the hazard rate?
The hazard function may not seem like an exciting variable to model but other indicators of interest, such as the survival function, are derived from the hazard rate. Once we have modeled the hazard rate we can easily obtain these other functions of interest.