The estimation of difference between two restricted mean lifetimes for interval-censored data

• Main Authors: YU,SHI-HAN, 余詩涵
• Other Authors: CHANG,YU-MEI
• Format: Others
• Language: zh-TW
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/z2wgbm

碩士 === 東海大學 === 統計學系 === 107 === Comparing the difference between two groups of treatment is widely used in medical research. In practice, the risk ratio of the two groups of treatment can change with time. For example, for the comparison between the effect of surgical treatment and drug treatment in coronary patients, the mortality rate of surgical treatment is higher than drug treatment in the early stage while the outcome can be reversed in the late stage. In this situation, it is well known that log rank test has low power of detecting the survival difference between the two treatments. One alternative is to consider the restricted mean survival time (rmst) between the two groups, which can be estimated based on nonparametric or semiparametric approach. In this article, for mixed interval censored data, we consider two approaches to constructing confidence intervals for the difference of rmst between two treatment groups. The first approach is based on the estimated difference of two rmsts, which are obtained using Turnbull’s nonparametric maximum likelihood estimator (NPMLE). The second approach is based on pseudo-observation scheme, which also relies on delete-one jackknife pseudo-observation of Turnbull’s NPMLE. Simulation results indicate that the first approach performs well while the second approach gives conservative intervals since sandwich variance estimators overestimate the true variances. Both methods are applied to HIV data for illustration.