Chapter 7 Survival Analysis
In this chapter, you will learn how to:
- Identify a time-to-event outcome;
- Identify types and mechanisms of censoring;
- Interpret the survival and hazard functions;
- Use the Kaplan-Meier method to estimate the survival function;
- Use the log-rank test to compare survival between groups;
- Visualize the Kaplan-Meier estimate of the survival function;
- Visualize the estimated hazard function;
- Fit a Cox proportional hazards regression model, including the following:
- Write and interpret the Cox regression equation;
- Estimate unadjusted and adjusted hazard ratios;
- Estimate the probability that an event has not yet occurred as of a given time;
- Estimate the hazard of an event relative to a reference group;
- Visualize the Cox regression estimate of the survival function;
- Test interactions between predictors;
- Incorporate time-varying predictors;
- Check the proportional hazards assumption;
- Allow non-proportional hazards using a time interaction or stratification;
- Check the linearity assumption, examine outliers, and identify influential observations; and
- Appropriately summarize the methods and results.
To use the code in this chapter, first load tidyverse
.
library(tidyverse)