Time-Varying Covariates in Survival Models
A practical guide to time-varying covariates in survival analysis, including extended Cox models, counting-process data, start-stop intervals, treatment exposure, time-dependent laboratory measurements, landmark analysis, immortal time bias, R and SAS implementation, and interpretation.
Testing the Proportional Hazards Assumption
A practical guide to testing the proportional hazards assumption in Cox regression, including Schoenfeld residuals, graphical diagnostics, time-by-covariate interactions, log-minus-log plots, interpretation, R and SAS implementations, and a complete clinical example.
Surrogate Endpoints in Survival Analysis
A practical guide to surrogate endpoints in survival analysis, including progression-free survival, overall survival, validation of surrogate endpoints, Prentice criteria, trial-level and individual-level surrogacy, treatment effects, correlation, meta-analysis, and oncology examples.
Restricted Mean Survival Time (RMST)
A practical guide to Restricted Mean Survival Time (RMST), including the RMST definition, Kaplan-Meier integration, RMST difference and ratio, interpretation, hypothesis testing, confidence intervals, clinical trial applications, R implementation, and worked examples.
Progression-Free Survival vs. Overall Survival
A practical clinical biostatistics guide to progression-free survival versus overall survival, including endpoint definitions, censoring, hazard ratios, Kaplan-Meier interpretation, treatment effects, common pitfalls, and oncology trial examples.
Milestone Survival Analysis in Oncology Trials
A practical guide to milestone survival analysis in oncology trials, including fixed-time overall survival and progression-free survival probabilities, Kaplan-Meier estimation, confidence intervals, treatment comparisons, censoring, estimands, and R and SAS implementation.
Log-Rank Test for Comparing Survival Curves
A practical guide to the log-rank test for comparing survival curves, including hypotheses, observed versus expected events, the test statistic, worked clinical example, interpretation, assumptions, stratified log-rank tests, and common mistakes.
Landmark Analysis in Survival Studies
A practical guide to landmark analysis in survival studies, including landmark time selection, time-dependent exposure, immortal time bias, Kaplan–Meier analysis, landmark Cox models, interpretation, worked examples, and common pitfalls.
Interval-Censored Survival Data Analysis
A practical guide to interval-censored survival data analysis, including likelihood construction, Turnbull
Hazard Ratio Interpretation for Clinicians
A practical guide for clinicians to interpreting hazard ratios from survival analyses, including relative hazard, confidence intervals, proportional hazards, absolute risk, Kaplan-Meier curves, nonproportional hazards, and common interpretation mistakes.