Survival Analysis Using SAS

CHAPTER 8

Heterogeneity, Repeated Events, and Other Topics

Introduction

Unobserved Heterogeneity

Repeated Events

Generalized R² 282

Sensitivity Analysis for Informative Censoring

INTRODUCTION

This chapter deals with several issues that arise for all the methods that we have previously discussed. The first two issues—heterogeneity and repeated events—are closely related. One problem with the models that we have been considering is that biological and social entities usually differ in ways that are not fully captured by the model. This unobserved heterogeneity can produce misleading estimates of hazard functions and attenuated estimates of covariate effects. When individuals can experience more than one event, unobserved heterogeneity can also ...