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  • Exploring Causal Effects of Hormone‐ and Radio‐Treatments in an Observational Study of Breast Cancer Using Copula‐Based Semi‐Competing Risks Models

This content will become publicly available on June 1, 2026

Title: Exploring Causal Effects of Hormone‐ and Radio‐Treatments in an Observational Study of Breast Cancer Using Copula‐Based Semi‐Competing Risks Models
ABSTRACT Breast cancer patients may experience relapse or death after surgery during the follow‐up period, leading to dependent censoring of relapse. This phenomenon, known as semi‐competing risk, imposes challenges in analyzing treatment effects on breast cancer and necessitates advanced statistical tools for unbiased analysis. Despite progress in estimation and inference within semi‐competing risks regression, its application to causal inference is still in its early stages. This article aims to propose a frequentist and semi‐parametric framework based on copula models that can facilitate valid causal inference, net quantity estimation and interpretation, and sensitivity analysis for unmeasured factors under right‐censored semi‐competing risks data. We also propose novel procedures to enhance parameter estimation and its applicability in practice. After that, we apply the proposed framework to a breast cancer study and detect the time‐varying causal effects of hormone‐ and radio‐treatments on patients' relapse and overall survival. Moreover, extensive numerical evaluations demonstrate the method's feasibility, highlighting minimal estimation bias and reliable statistical inference.  more » « less
Award ID(s):
2412577
PAR ID:
10628818
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Statistics in Medicine (2025)
Date Published:
Journal Name:
Statistics in Medicine
Volume:
44
Issue:
13-14
ISSN:
0277-6715
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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