How to calculate (average) hazard ratios for parametric survival models based on the R/flexsurv package

This tutorial [PDF] aims to support the interpretation of parametric time-to-event models by explaining how to calculate the hazard ratio, which is a conventional effect size to evaluate clinical relevance of treatment effects. The following distributions, which are considered most important for health economic analyses, are implemented in the flexsurv package (cf ?flexsurvreg): exp: exponential…