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Full-Text Articles in Biostatistics
An Interval-Censored Proportional Hazards Model, John M. Williamson, Hung-Mo Lin, Hae-Young Kim
An Interval-Censored Proportional Hazards Model, John M. Williamson, Hung-Mo Lin, Hae-Young Kim
NYMC Faculty Publications
We fit a Cox proportional hazards (PH) model to interval-censored survival data by first subdividing each individual's failure interval into non-overlapping sub-intervals. Using the set of all interval endpoints in the data set, those that fall into the individual's interval are then used as the cut points for the sub-intervals. Each sub-interval has an accompanying weight calculated from a parametric Weibull model based on the current parameter estimates. A weighted PH model is then fit with multiple lines of observations corresponding to the sub-intervals for each individual, where the lower end of each sub-interval is used as the observed failure …
Linear Regression Of Censored Length-Biased Lifetimes, Ying Qing Chen, Yan Wang
Linear Regression Of Censored Length-Biased Lifetimes, Ying Qing Chen, Yan Wang
UW Biostatistics Working Paper Series
Length-biased lifetimes may be collected in observational studies or sample surveys due to biased sampling scheme. In this article, we use a linear regression model, namely, the accelerated failure time model, for the population lifetime distributions in regression analysis of the length-biased lifetimes. It is discovered that the associated regression parameters are invariant under the length-biased sampling scheme. According to this discovery, we propose the quasi partial score estimating equations to estimate the population regression parameters. The proposed methodologies are evaluated and demonstrated by simulation studies and an application to actual data set.