Survival Analysis Using SAS®: A Practical Guide

Sensitivity Analysis for Informative Censoring

In Chapters 2 and 6, we discussed the relatively intractable problem of informative censoring. Let’s quickly review the problem. Suppose that just before some particular time t there are 50 individuals who are still at risk of an event. Of those 50 individuals, 5 are censored at time t. Suppose further that 20 of the 50 at risk have covariate values that are identical to those of the 5 who are censored. We say that censoring is informative if the 5 who are censored are a biased subsample of the 20 individuals with the same covariate values. That is, they have hazards that are systematically higher or lower than those who were not censored. Informative censoring can lead to parameter estimates that ...