Journal of Statistical Theory and Practice

, Volume 7, Issue 3, pp 496–504 | Cite as

Revisit Kaplan-Meier Estimator in Estimating QAL Survival Distributions

  • J. WangEmail author
  • Y. Li


Quality-adjusted lifetime (QAL) is an important component in evaluation of clinical trials. In a seminal paper, Gelber et al. (1989) claimed that the Kaplan-Meier estimator is inconsistent in estimating the distribution of QAL under the presence of censoring. However, in this article, we show that, with appropriate censoring indexing, the Kaplan-Meier estimator actually is consistent in some practically important QAL data settings.


Kaplan-Meier estimator Quality-adjusted lifetime Survival analysis Zhao-Tsiatis estimator 


Primary 62N02 Secondary 62G05 


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Copyright information

© Grace Scientific Publishing 2013

Authors and Affiliations

  1. 1.Department of MathematicsKean UniversityUnionUSA
  2. 2.Department of Mathematical SciencesUniversity of Houston-Clear LakeHoustonUSA

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