Survival analysis


Cox proportional hazards
  • time-varying covariates and censoring
  • continuously time-varying covariates
  • conventional or robust estimates of variance
  • stratified estimation
  • sampling weights
  • four ways to handle ties: Breslow, exact partial likelihood, exact marginal likelihood, and Efron
  • martingale, efficient score, Cox–Snell, Schoenfeld, and deviance residuals
  • tests for proportional hazards
  • estimates of baseline survival, hazard, and cumulative hazard functions
  • shared frailty models
  • Harrell's C and Somers' D statistics measuring concordance

Parametric survival models

  • exponential
  • Weibull
  • Gompertz
  • lognormal
  • log-logistic
  • generalized log-gamma
  • martingale-like, score, Cox–Snell, Schoenfeld, and deviance residuals
  • plots of predicted survival, hazard, and cumulative hazard functions
  • individual-level frailty
  • group-level or shared frailty
  • stratified models
  • linear constraints

Features of survival models

  • single- or multiple-failure data
  • left truncation
  • right-censoring
  • time-varying regressors
  • gaps
  • recurring events
  • start–stop format
  • different types of failure events
  • multiple time scales allowed
  • conventional or robust estimates of variance
 
Kaplan–Meier and Nelson–Aalen
  • graph estimates and confidence intervals
  • list estimates and confidence intervals
  • test (log-rank, Mantel–Haenszel, Wilcoxon–Breslow, Tarone–Ware, Fleming–Harrington, Peto–Peto–Prentice)
  • test for trend
  • calculate level and confidence interval of survivor function
  • report mean survival time and confidence interval
  • Cox regression-adjusted estimates

Summary tables

  • time at risk, incidence rate, number of subjects, 25th, 50th, and 75th percentiles of survival time
  • incidence rate ratio and difference
  • life tables
  • rates and SMRs by one or more categorical variables
  • stratified rate ratios

Utilities

  • create nested case–control datasets
  • split and join time records
  • convert snapshot data into time-span data
  • calculate person-time (person-years), incidence rates, and standardized mortality/morbidity ratios (SMR)

Predictions

  • mean or median time to failure
  • mean or median log time
  • hazard
  • hazard ratios
  • survival probabilities

Marginal effects

  • marginal effects and elasticities
  • standard errors and confidence intervals
  • at means or specified covariate values
  • for any predicted statistic

A survival example session


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