Abstract:
:Bivariate survival data arise, for example, in twin studies and studies of both eyes or ears of the same individual. Often it is of interest to regress the survival times on a set of predictors. In this paper we extend Wei and Tanner's multiple imputation approach for linear regression with univariate censored data to bivariate censored data. We formulate a class of censored bivariate linear regression methods by iterating between the following two steps: 1. the data is augmented by imputing survival times for censored observations; 2. a linear model is fit to the imputed complete data. We consider three different methods to implement these two steps. In particular, the marginal (independence) approach ignores the possible correlation between two survival times when estimating the regression coefficient. To improve the efficiency, we propose two methods that account for the correlation between the survival times. First, we improve the efficiency by using generalized least squares regression in step 2. Second, instead of generating data from an estimate of the marginal distribution we generate data from a bivariate log-spline density estimate in step 1. Through simulation studies we find that the performance of the two methods that take the dependence into account is close and that they are both more efficient than the marginal approach. The methods are applied to a data set from an otitis media clinical trial.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Pan W,Kooperberg Cdoi
10.1002/(sici)1097-0258(19991130)18:22<3111::aid-ssubject
Has Abstractpub_date
1999-11-30 00:00:00pages
3111-21issue
22eissn
0277-6715issn
1097-0258pii
10.1002/(SICI)1097-0258(19991130)18:22<3111::AID-Sjournal_volume
18pub_type
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