Abstract:
:To compare the survival functions based on right-truncated data, Lagakos et al. proposed a weighted logrank test based on a reverse time scale. This is in contrast to Bilker and Wang, who suggested a semi-parametric version of the Mann-Whitney test by assuming that the distribution of truncation times is known or can be estimated parametrically. The approach of Lagakos et al. is simple and elegant, but the weight function in their method depends on the underlying cumulative hazard functions even under proportional hazards models. On the other hand, a semi-parametric test may have better efficiency, but it may be sensitive to misspecification of the distribution of truncation times. Therefore, this paper proposes a non-parametric test statistic based on the integrated weighted difference between two estimated survival functions in forward time. The comparative results from a simulation study are presented and the implementation of these methods to a real data set is demonstrated.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Chi Y,Tsai WY,Chiang CLdoi
10.1002/sim.2556subject
Has Abstractpub_date
2007-02-20 00:00:00pages
812-27issue
4eissn
0277-6715issn
1097-0258journal_volume
26pub_type
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