A marginal mixed baseline hazards model for multivariate failure time data

In multivariate failure time data analysis, a marginal regression modeling approach is often preferred to avoid assumptions on the dependence structur e among correlated failure times. In this paper, a marginal mixed baseline hazards model is introduced. Estimating equations are proposed for the esti mation of the marginal hazard ratio parameters. The proposed estimators are shown to be consistent and asymptotically Gaussian with a robust covarianc e matrix that can be consistently estimated. Simulation studies indicate th e adequacy of the proposed methodology for practical sample sizes. The meth odology is illustrated with a data set from the Framingham Heart Study.