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Related papers: Imbalanced Randomization in Clinical Trials

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Two commonly used methods for improving precision and power in clinical trials are stratified randomization and covariate adjustment. However, many trials do not fully capitalize on the combined precision gains from these two methods, which…

We consider the conditional randomization test as a way to account for covariate imbalance in randomized experiments. The test accounts for covariate imbalance by comparing the observed test statistic to the null distribution of the test…

Randomized controlled trials are not only the golden standard in medicine and vaccine trials but have spread to many other disciplines like behavioral economics, making it an important interdisciplinary tool for scientists. When designing…

Methodology · Statistics 2021-11-30 Tassilo Schwarz

We consider the performance of the difference-in-means estimator in a two-arm randomized experiment under common experimental endpoints such as continuous (regression), incidence, proportion and survival. We examine performance under both…

Statistics Theory · Mathematics 2025-07-08 David Azriel , Abba M. Krieger , Adam Kapelner

Randomized saturation designs are a family of designs which assign a possibly different treatment proportion to each cluster of a population at random. As a result, they generalize the well-known (stratified) completely randomized designs…

Methodology · Statistics 2022-03-21 Chencheng Cai , Jean Pouget-Abadie , Edoardo M. Airoldi

Targeted therapies on the basis of genomic aberrations analysis of the tumor have shown promising results in cancer prognosis and treatment. Regardless of tumor type, trials that match patients to targeted therapies for their particular…

Applications · Statistics 2018-04-18 Yanxun Xu , Peter Mueller , Apostolia M Tsimberidou , Donald Berry

This study examines the application of Bayesian approach in the context of clinical trials, emphasizing their increasing importance in contemporary biomedical research. While conventional frequentist approach provides a foundational basis…

Methodology · Statistics 2026-01-16 Paramahansa Pramanik , Arnab Kumar Maity , Anjan Mandal , Haley Kate Robinson

In recent years, real-world external controls have grown in popularity as a tool to empower randomized placebo-controlled trials, particularly in rare diseases or cases where balanced randomization is unethical or impractical. However, as…

Methodology · Statistics 2024-11-14 Chenyin Gao , Shu Yang , Mingyang Shan , Wenyu Ye , Ilya Lipkovich , Douglas Faries

Clinical trial adaptation refers to any adjustment of the trial protocol after the onset of the trial. The main goal is to make the process of introducing new medical interventions to patients more efficient by reducing the cost and the…

Machine Learning · Computer Science 2014-11-17 Ognjen Arandjelovic

We study the design of multi-armed parallel group clinical trials to estimate personalized treatment rules that identify the best treatment for a given patient with given covariates. Assuming that the outcomes in each treatment arm are…

Statistics Theory · Mathematics 2022-07-13 David Azriel , Yosef Rinott , Martin Posch

Contrary to traditional deterministic notions of algorithmic fairness, this paper argues that fairly allocating scarce resources using machine learning often requires randomness. We address why, when, and how to randomize by proposing…

Computers and Society · Computer Science 2024-06-21 Shomik Jain , Kathleen Creel , Ashia Wilson

This paper studies a two-stage model of experimentation, where the researcher first samples representative units from an eligible pool, then assigns each sampled unit to treatment or control. To implement balanced sampling and assignment,…

Econometrics · Economics 2023-08-22 Max Cytrynbaum

Background: It has long been advised to account for baseline covariates in the analysis of confirmatory randomised trials, with the main statistical justifications being that this increases power and, when a randomisation scheme balanced…

Methodology · Statistics 2021-12-09 Tim P. Morris , A. Sarah Walker , Elizabeth J. Williamson , Ian R. White

Adaptive sample size re-estimation, early stopping, and trial re-design at interim analyses can reduce expected sample sizes in randomised trials. Cluster randomised trials, in which groups of participants are randomly allocated to…

Methodology · Statistics 2026-03-09 Samuel I. Watson , James Martin

The allocation problem for multivariate stratified random sampling as a problem of stochastic matrix integer mathematical programming is considered. With these aims the asymptotic normality of sample covariance matrices for each strata is…

Statistics Theory · Mathematics 2011-05-18 Jose A. Diaz-Garcia , Rogelio Ramos-Quiroga

An important objective in the development of targeted therapies is to identify the populations where the treatment under consideration has positive benefit risk balance. We consider pivotal clinical trials, where the efficacy of a treatment…

In modern scientific research, small-scale studies with limited participants are increasingly common. However, interpreting individual outcomes can be challenging, making it standard practice to combine data across studies using random…

Statistics Theory · Mathematics 2025-11-04 Lucas Kania , Larry Wasserman , Sivaraman Balakrishnan

While a broad range of techniques have been proposed to tackle distribution shift, the simple baseline of training on an $\textit{undersampled}$ balanced dataset often achieves close to state-of-the-art-accuracy across several popular…

Machine Learning · Computer Science 2023-06-21 Niladri S. Chatterji , Saminul Haque , Tatsunori Hashimoto

Observed events in recommendation are consequence of the decisions made by a policy, thus they are usually selectively labeled, namely the data are Missing Not At Random (MNAR), which often causes large bias to the estimate of true outcomes…

Machine Learning · Computer Science 2021-10-05 Zifeng Wang , Xi Chen , Rui Wen , Shao-Lun Huang

In the experimental design literature, Neyman allocation refers to the practice of allocating units into treated and control groups, potentially in unequal numbers proportional to their respective standard deviations, with the objective of…

Methodology · Statistics 2026-01-15 Jinglong Zhao
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