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PubMed · 11424300

Survival analysis with time-varying relative risks: a tree-based approach.

R Xu·S Adak
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Abstract

A tree-based method for estimating time-varying effects of baseline patient characteristics on survival is introduced. A Cox-type model for censored survival data is used in which the time-varying relative risks are modelled as piecewise constants. The tree method consists of three steps: 1. Growing the tree, in which a fast algorithm using maximized score statistics is utilized to determine the optimal change points; 2. A pruning algorithm is applied to obtain more parsimonious models; 3. Selection of a final tree, which may be either via bootstrap resampling or based on a measure of explained variation. The piecewise constant model is more suitable for clinical interpretation of the regression parameters than the more continuously time-varying models (spline, loess, etc.) that have been proposed previously.

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AlgorithmsBreast NeoplasmsFemaleFranceHumansPrognosisProportional Hazards ModelsRegression AnalysisRiskSurvival AnalysisJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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R Xu, S Adak. 2001. Survival analysis with time-varying relative risks: a tree-based approach.. https://pubmed.ncbi.nlm.nih.gov/11424300/

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