Survival Analysis
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- Time-varying covariates and censoring
- Continuously time-varying covariates
- Conventional or robust estimates of variance
- Stratified estimation
- Sampling weights and survey data
- 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
- Factor variablesv New
- Multiple imputation New
Competing-risks regression New
- Fine and Gray proportional subhazards model
- Time-varying covariates
- Cumulative-incidence graphs
- Subhazard ratios
- Multiple imputation
- Factor variables
- Constraints
Parametric survival models
- Exponential
- Weibull
- Gompertz
- Lognormal
- Loglogistic
- Generalized log-gamma
- Sampling weights and survey data
- 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 with risk tables Updated
- 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
Power analysis
- Solve for sample size, power, or effect size
- Log-rank test of survival curves
- Cox proportional hazards model
- Exponential regression
- 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 analysis New
- Estimated marginal means
- Predictive margins
- Average marginal effects
- Average adjusted predictions