Nonparametric quantile estimation with correlated failure time data.
In biomedical studies, correlated failure time data arise often. Although point and confidence interval estimation for quantiles with independent censored failure time data have been extensively studied, estimation for quantiles with correlated failure time data has not been developed. In this article, we propose a nonparametric estimation method for quantiles with correlated failure time data. We derive the asymptotic properties of the quantile estimator and propose confidence interval estimators based on the bootstrap and kernel smoothing methods. Simulation studies are carried out to investigate the finite sample properties of the proposed estimators. Finally, we illustrate the proposed method with a data set from a study of patients with otitis media.
Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7420, USA. cai@bios.unc.edu
Jianwen
J
Cai
Jinheum
J
Kim
D002675:Child, Preschool; D016000:Cluster Analysis; D006801:Humans; D015233:Models, Statistical; D010033:Otitis Media / Q000601:surgery; D016032:Randomized Controlled Trials as Topic; D018709:Statistics, Nonparametric; D016019:Survival Analysis; D013997:Time Factors; D017211:Treatment Failure