Premium
Accounting for bias due to a non‐ignorable tracing mechanism in a retrospective breast cancer cohort study
Author(s) -
Titman Andrew C.,
Lancaster Gillian A.,
Carmichael Katie,
Scutt Diane
Publication year - 2010
Publication title -
statistics in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.996
H-Index - 183
eISSN - 1097-0258
pISSN - 0277-6715
DOI - 10.1002/sim.4118
Subject(s) - truncation (statistics) , statistics , breast cancer , retrospective cohort study , tracing , cohort , markov chain , piecewise , econometrics , computer science , medicine , mathematics , cancer , mathematical analysis , operating system
We consider the analysis of competing risks in a retrospective breast cancer cohort study where tracing of patients is dependent on survival to a pre‐specified truncation time. We demonstrate that if ignored, the observed cause‐specific hazards will become distorted before the truncation time. Two approaches to account for the tracing bias are considered. First, a likelihood‐based method using piecewise constant transition intensities under a Markov assumption. Second, a pseudo‐likelihood method using inverse probability of tracing weights. For the breast cancer example, both methods improve the precision of estimates compared with a conventional approach based on excluding patients. Copyright © 2010 John Wiley & Sons, Ltd.