UCL Discovery
UCL home » Library Services » Electronic resources » UCL Discovery

Re-randomisation trials in multi-episode settings: Estimands and independence estimators

Kahan, Brennan C; White, Ian R; Hooper, Richard; Eldridge, Sandra; (2022) Re-randomisation trials in multi-episode settings: Estimands and independence estimators. Statistical Methods in Medical Research 10.1177/09622802221094140. Green open access

[thumbnail of 09622802221094140.pdf]
Preview
PDF
09622802221094140.pdf - Published Version

Download (604kB) | Preview

Abstract

Often patients may require treatment on multiple occasions. The re-randomisation design can be used in such multi-episode settings, as it allows patients to be re-enrolled and re-randomised for each new treatment episode they experience. We propose a set of estimands that can be used in multi-episode settings, focusing on issues unique to multi-episode settings, namely how each episode should be weighted, how the patient's treatment history in previous episodes should be handled, and whether episode-specific effects or average effects across all episodes should be used. We then propose independence estimators for each estimand, and show the manner in which many re-randomisation trials have been analysed in the past (a simple comparison between all intervention episodes vs. all control episodes) corresponds to a per-episode added-benefit estimand, that is, the average effect of the intervention across all episodes, over and above any benefit conferred from the intervention in previous episodes. We show this estimator is generally unbiased, and describe when other estimators will be unbiased. We conclude that (i) consideration of these estimands can help guide the choice of which analysis method is most appropriate; and (ii) the re-randomisation design with an independence estimator can be a useful approach in multi-episode settings.

Type: Article
Title: Re-randomisation trials in multi-episode settings: Estimands and independence estimators
Location: England
Open access status: An open access version is available from UCL Discovery
DOI: 10.1177/09622802221094140
Publisher version: https://doi.org/10.1177/09622802221094140
Language: English
Additional information: https://creativecommons.org/licenses/by/4.0/This article is distributed under the terms of the Creative Commons Attribution 4.0 License (https://creativecommons.org/licenses/by/4.0/) which permits any use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access page (https://us.sagepub.com/en-us/nam/open-access-at-sage).
Keywords: Estimand, re-randomisation design, randomised trial, multi-episode setting, informative cluster size
UCL classification: UCL
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Population Health Sciences > Inst of Clinical Trials and Methodology > MRC Clinical Trials Unit at UCL
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences > Faculty of Population Health Sciences > Inst of Clinical Trials and Methodology
UCL > Provost and Vice Provost Offices > School of Life and Medical Sciences
URI: https://discovery.ucl.ac.uk/id/eprint/10147757
Downloads since deposit
26Downloads
Download activity - last month
Download activity - last 12 months
Downloads by country - last 12 months

Archive Staff Only

View Item View Item