Bayesian Mediation Analysis for Individualized Treatment Rules
- URL: http://arxiv.org/abs/2607.28804v1
- Date: Thu, 30 Jul 2026 19:59:18 GMT
- Title: Bayesian Mediation Analysis for Individualized Treatment Rules
- Abstract summary: The value of an individualized treatment rule (ITR) is useful for assessing average clinical benefit but does not explain how the benefit of a rule is generated.<n>We propose a causal mediation framework for decomposing the value contrast between a prespecified candidate ITR and a clinically meaningful reference rule into direct and indirect components.
- Score: 0.5999777817331315
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The value of an individualized treatment rule (ITR), defined as the expected outcome under treatment assignment according to the rule, is useful for assessing average clinical benefit but does not explain how the benefit of a rule is generated. We propose a causal mediation framework for decomposing the value contrast between a prespecified candidate ITR and a clinically meaningful reference rule into direct and indirect components. Using rule-specific nested potential outcomes, we define natural direct and indirect rule effects that quantify the extent to which the improvement in value arises through pathways operating directly on the outcome versus through a specified mediator. We give identification conditions under which these components are identified by a rule-level mediation g-formula. For estimation, we adapt Bayesian causal mediation forests to obtain posterior inference for the value contrast and its path-specific components. Our simulations demonstrate that the proposed estimator achieved near-nominal credible interval coverage with decreasing bias and root mean squared error as sample size increased in settings with varying direct and mediated contributions. We further illustrate the method using data from the TRIUMPH trial, decomposing the cognitive benefit of a lifestyle intervention rule through candidate neurovascular, cardiorespiratory, and behavioral mediators. The proposed framework complements optimal ITR learning with explanation using mediation, providing a natural approach for mechanistic evaluation of ITRs.
Related papers
- RRPO: Reference-Relative Policy Optimization with Stratified Conditional Rollouts [84.20747697259326]
Group Relative Policy Optimization (GRPO) has shown strong effectiveness in reinforcement learning from verifiable feedback.<n>We propose textbfReference-Relative Policy Optimization (RRPO), which generalizes GRPO by replacing direct correctness-based advantage construction with reference-relative contrastive comparisons.<n>We evaluate RRPO using anchor-based contrastive advantages throughout policy optimization, without relying on task ground-truth verifiers.
arXiv Detail & Related papers (2026-07-20T19:40:25Z) - Overlap-Adaptive Regularization for Conditional Average Treatment Effect Estimation [59.153491256972806]
State-of-the-art methods for CATE estimation often perform poorly in the presence of low overlap.<n>We introduce Overlap-Adaptive Regularization (OAR) that regularizes target models proportionally to overlap weights.<n>Our OAR significantly improves CATE estimation in low-overlap settings in comparison to constant regularization.
arXiv Detail & Related papers (2025-09-29T15:56:24Z) - Human-Guided Shade Artifact Suppression in CBCT-to-MDCT Translation via Schrödinger Bridge with Conditional Diffusion [1.5869861104370917]
We present a novel framework for CBCT-to-MDCT translation, grounded in the Schrodinger Bridge (SB) formulation.<n>Our approach explicitly enforces boundary consistency between CBCT inputs and pseudo targets, ensuring both anatomical fidelity and perceptual controllability.
arXiv Detail & Related papers (2025-07-15T06:44:53Z) - Beyond the ATE: Interpretable Modelling of Treatment Effects over Dose and Time [46.2482873419289]
We propose a framework for modelling treatment effect trajectories as smooth surfaces over dose and time.<n>Our approach decouples the estimation of trajectory shape from the specification of clinically relevant properties.<n>We show that our method yields accurate, interpretable, and editable models of treatment dynamics.
arXiv Detail & Related papers (2025-07-09T20:33:33Z) - Dynamic Local Average Treatment Effects [19.014535120129338]
We consider Dynamic Treatment Regimes (DTRs) with One Sided Noncompliance in digital recommendations and adaptive medical trials.<n>We provide nonparametric identification, estimation, and inference for Dynamic Local Average Treatment Effects (LATEs)<n>We show that the assumptions are sufficient to identify Dynamic LATEs for treating in multiple time periods.
arXiv Detail & Related papers (2024-05-02T16:52:09Z) - Fusing Individualized Treatment Rules Using Secondary Outcomes [7.657053163626398]
We learn an ITR that not only maximizes the value function for the primary outcome, but also approximates the optimal rule for the secondary outcomes.
Two algorithms are proposed to estimate the ITR using surrogate loss functions.
We prove that the agreement rate between the estimated ITR of the primary outcome and the optimal ITRs of the secondary outcomes converges to the true agreement rate faster than if the secondary outcomes are not taken into consideration.
arXiv Detail & Related papers (2024-02-13T22:16:36Z) - Improved Policy Evaluation for Randomized Trials of Algorithmic Resource
Allocation [54.72195809248172]
We present a new estimator leveraging our proposed novel concept, that involves retrospective reshuffling of participants across experimental arms at the end of an RCT.
We prove theoretically that such an estimator is more accurate than common estimators based on sample means.
arXiv Detail & Related papers (2023-02-06T05:17:22Z) - Neighborhood Adaptive Estimators for Causal Inference under Network Interference [109.17155002599978]
We consider the violation of the classical no-interference assumption with units connected by a network.<n>For tractability, we consider a known network that describes how interference may spread.
arXiv Detail & Related papers (2022-12-07T14:53:47Z) - Evaluating Treatment Prioritization Rules via Rank-Weighted Average
Treatment Effects [24.258855352542096]
We propose rank-weighted average treatment effect metrics as a simple and general family of metrics for comparing and testing the quality of treatment prioritization rules.
RATE metrics are agnostic to how the prioritization rules were derived, and only assess how well they identify individuals that benefit the most from treatment.
We showcase RATE in the context of a number of applications, including optimal targeting of aspirin to stroke patients.
arXiv Detail & Related papers (2021-11-15T18:22:35Z) - Post-Contextual-Bandit Inference [57.88785630755165]
Contextual bandit algorithms are increasingly replacing non-adaptive A/B tests in e-commerce, healthcare, and policymaking.
They can both improve outcomes for study participants and increase the chance of identifying good or even best policies.
To support credible inference on novel interventions at the end of the study, we still want to construct valid confidence intervals on average treatment effects, subgroup effects, or value of new policies.
arXiv Detail & Related papers (2021-06-01T12:01:51Z) - Median Optimal Treatment Regimes [7.241149193573696]
We propose a new median optimal treatment regime that treats individuals whose conditional median is higher under treatment.
This ensures that optimal decisions for individuals from the same group are not overly influenced by a small fraction of the group.
We introduce a new measure of value, the Average Conditional Median Effect (ACME), which summarizes across-group median treatment outcomes of a policy.
arXiv Detail & Related papers (2021-03-02T15:26:20Z) - Individual Treatment Prescription Effect Estimation in a Low Compliance
Setting [11.672067762133299]
Individual Treatment Effect estimation is an extensively researched problem, with applications in various domains.
We propose a new approach for the estimation of the IPE that takes advantage of observed compliance information to prevent signal fading.
We conduct experiments on both synthetic and real-world datasets that highlight the benefit of the approach, which consistently improves state-of-the-art in low compliance settings.
arXiv Detail & Related papers (2020-08-07T15:53:00Z) - Comment: Entropy Learning for Dynamic Treatment Regimes [58.442274475425144]
JSLZ's approach leverages a rejection-and-sampling estimate of the value of a given decision rule based on inverse probability (IPW) and its interpretation as a weighted (or cost-sensitive) classification.
Their use of smooth classification surrogates enables their careful approach to analyzing distributions.
The IPW estimate is problematic as it leads to weights that discard most of the data and are extremely variable on whatever remains.
arXiv Detail & Related papers (2020-04-06T16:11:05Z) - Almost-Matching-Exactly for Treatment Effect Estimation under Network
Interference [73.23326654892963]
We propose a matching method that recovers direct treatment effects from randomized experiments where units are connected in an observed network.
Our method matches units almost exactly on counts of unique subgraphs within their neighborhood graphs.
arXiv Detail & Related papers (2020-03-02T15:21:20Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.