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Published in: Trials 1/2014

Open Access 01-12-2014 | Study protocol

Methodological survey of designed uneven randomization trials (DU-RANDOM): a protocol

Authors: Darong Wu, Elie A Akl, Gordon H Guyatt, Philip J Devereaux, Romina Brignardello-Petersen, Barbara Prediger, Krupesh Patel, Namrata Patel, Taoying Lu, Yuan Zhang, Maicon Falavigna, Nancy Santesso, Reem A Mustafa, Qi Zhou, Matthias Briel, Holger J Schünemann

Published in: Trials | Issue 1/2014

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Abstract

Background

Although even randomization (that is, approximately 1:1 randomization ratio in study arms) provides the greatest statistical power, designed uneven randomization (DUR), (for example, 1:2 or 1:3) is used to increase participation rates. Until now, no convincing data exists addressing the impact of DUR on participation rates in trials. The objective of this study is to evaluate the epidemiology and to explore factors associated with DUR.

Methods

We will search for reports of RCTs published within two years in 25 general medical journals with the highest impact factor according to the Journal Citation Report (JCR)-2010. Teams of two reviewers will determine eligibility and extract relevant information from eligible RCTs in duplicate and using standardized forms. We will report the prevalence of DUR trials, the reported reasons for using DUR, and perform a linear regression analysis to estimate the association between the randomization ratio and the associated factors, including participation rate, type of informed consent, clinical area, and so on.

Discussion

A clearer understanding of RCTs with DUR and its association with factors in trials, for example, participation rate, can optimize trial design and may have important implications for both researchers and users of the medical literature.
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Metadata
Title
Methodological survey of designed uneven randomization trials (DU-RANDOM): a protocol
Authors
Darong Wu
Elie A Akl
Gordon H Guyatt
Philip J Devereaux
Romina Brignardello-Petersen
Barbara Prediger
Krupesh Patel
Namrata Patel
Taoying Lu
Yuan Zhang
Maicon Falavigna
Nancy Santesso
Reem A Mustafa
Qi Zhou
Matthias Briel
Holger J Schünemann
Publication date
01-12-2014
Publisher
BioMed Central
Published in
Trials / Issue 1/2014
Electronic ISSN: 1745-6215
DOI
https://doi.org/10.1186/1745-6215-15-33

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