mlsanityData to 7 Oct 2026

Bayesian fusion forests for heterogeneous treatment effects on survival from randomised and real-world data

arXiv 2607.29295 ↗First posted 31 Jul 2026stat.ME stat.MLcited by 0

Not on the map. Why?

Abstract (arXiv)

We develop the Bayesian fusion forest, a nonparametric framework to estimate heterogeneous treatment effects on survival outcomes by combining a randomised controlled trial and real-world data. The framework relaxes the unconfoundedness assumption on the real-world data by assuming instead that the treatment effect transports across the two sources. Our method opens up right- and interval-censored outcomes to data fusion. We model the survival time with an accelerated failure time decomposition into a shared baseline prognosis, a source-specific deviation, a treatment effect, and a confounding function. The confounding function absorbs the confounding bias in the real-world data. Each component receives a Bayesian tree ensemble prior. The shared baseline prognosis borrows strength across sources, while the deviation captures between-source heterogeneity. A hierarchical Dirichlet process mixture models the error distribution nonparametrically. A simulation study shows efficiency gains over a trial-only analysis across varying levels of confounding and between-source heterogeneity. We combine the ACTG 175 trial with the Multicenter AIDS Cohort Study to estimate the effect of combination antiretroviral therapy for HIV. The fusion identifies a benefit for nearly every patient whereas the trial alone is inconclusive.

Key facts. No citing papers in the map yet (data through 7 Oct 2026). Builds on 23 of its 63 references that are in the map. First posted on arXiv 31 Jul 2026.

Builds on

23 of 63 references.

References · 23

  1. 2017Meta-learners for Estimating Heterogeneous Treatment Effects using Machine Learningcited by 475
  2. 2017Automated versus do-it-yourself methods for causal inference: Lessons learned from a data analysis competitioncited by 106
  3. 2018Removing Hidden Confounding by Experimental Groundingcited by 64
  4. 2021Semiparametric counterfactual density estimationcited by 42
  5. 2017Bayesian regression tree models for causal inference: regularization, confounding, and heterogeneous effectscited by 41
  6. 2020Survival regression with accelerated failure time model in XGBoostcited by 37
  7. 2013bartMachine: Machine Learning with Bayesian Additive Regression Treescited by 24
  8. 2017Generalizing causal inferences from individuals in randomized trials to all trial-eligible individualscited by 24
  9. 2020Elastic Integrative Analysis of Randomized Trial and Real-World Data for Treatment Heterogeneity Estimationcited by 17
  10. 2017Individualized Treatment Effects with Censored Data via Fully Nonparametric Bayesian Accelerated Failure Time Modelscited by 13
  11. 2020Data fusion methods for the heterogeneity of treatment effect and confounding functioncited by 9
  12. 2019Model interpretation through lower-dimensional posterior summarizationcited by 5
11 more
  1. 2023Multi-Study R-Learner for Estimating Heterogeneous Treatment Effects Across Studies Using Statistical Machine Learningcited by 4
  2. 2020A flexible parametric accelerated failure time modelcited by 3
  3. 2021Incorporating External Data into the Analysis of Clinical Trials via Bayesian Additive Regression Treescited by 2
  4. 2024Causal-ICM: A Data Fusion Framework For Heterogeneous Treatment Effect Estimation With Multi-Task Gaussian Processescited by 2
  5. 2025Statistical Inference for Heterogeneous Treatment Effect with Right-censored Data from Synthesizing Randomized Clinical Trials and Real-world Datacited by 2
  6. 2024The causal interpretation of acceleration factorscited by 1
  7. 2025Integrative Analysis of High-dimensional RCT and RWD Subject to Censoring and Hidden Confoundingcited by 1
  8. 2025Quantifying uncertainty of individualized treatment effects in right-censored survival data: A comparison of Bayesian additive regression trees and causal survival forestcited by 1
  9. 2025Horseshoe Forests for High-Dimensional Causal Survival Analysiscited by 1
  10. 2025Counterfactual Survival Q-learning via Buckley-James Boosting, with Applications to ACTG 175 and CALGB 8923cited by 1
  11. 2026ShrinkageTrees: An R Package for Bayesian Tree Ensembles for Survival Analysis and Causal Inferencecited by 1

Built on by

Not cited yet.