An important means in the analysis of survival time data is the estimation and graphical
representation of survival probabilities. In this paper unifactorial parametric and
non-parametric survival curve estimators and two types of adjusted survival curves
based on a parametric multifactorial approach are applied to renal transplant data.
It is shown that the resulting survival curves can differ substantially. The unifactorial
survival curves yield biased results in case of serious disequilibrium in the data.
This drawback of the unifactorial methods has been overcome by the use of adjusted
survival curves which take possible distortions in the data set into account. The
benefits of adjusted survival curves in assessing potentially prognostic factors are
elucidated by the application to data from renal transplantation.
Key-words
Survival Times - Unifactorial Survival Curves - Adjusted Survival Curves - Renal Transplant
Data