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Featured article: Outcome pre-specification requires sufficient detail to guard against outcome switching in clinical trials

Prospectively specifying outcomes for a clinical trial helps guard against outcome switching. This case study from Brennan C Kahan (Queen Mary University of London) and Vipul Jairath (Western University) highlights the importance of including sufficient detail on these outcomes as small differences in interpretations can enable selective reporting for the most favorable result.


  1. Content type: Review


    Authors: Barbara Farrell, Sara Kenyon and Haleema Shakur

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Thematic series
Building capacity for evidence informed trial management
Edited by Dr Roberta Littleford and Prof Shaun Treweek

Thematic series
Stepped wedge randomized controlled trials
Edited by Prof David Torgerson

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Featured video: The COMET Initiative’s guide to selecting outcomes in clinical trials

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Aims and scope

Trials encompasses all aspects of the performance and findings of randomized controlled trials in health. Trials encourages full and transparent reporting of all research.  We publish articles on general trial methodology as well as protocols, commentaries and traditional results papers - regardless of outcome or significance of findings.

Thank you to our peer reviewers

The editors and staff of Trials would like to warmly thank our peer reviewers whose comments have helped to shape the journal.

Latest Tweets

Call for papers: Building capacity for evidence informed trial management

We are pleased to announce that Trials is accepting submissions for a new thematic series aimed at building the evidence base for trial management. Co-edited by Dr Roberta Littleford (University of Dundee, UK) and Prof Shaun Treweek (University of Aberdeen, UK), this series will include articles that report on what is currently known about effective trial management processes and how to make trial management more evidence-informed.

Call for papers: Big data for randomized trials

We are pleased to announce that Trials is accepting submissions for a new thematic series on using big data for randomized trials. Edited by Dr Lars Hemkens (University Hospital Basel, Switzerland), this series will consider articles that report on what is currently known about using big data or routinely collected data (such as electronic health records, registries or administrative databases) for randomized trials.

Call for papers: The future of pragmatic trials

We are pleased to announce that Trials is accepting submissions for a new thematic series on the future of pragmatic trials. Edited by Professor Marion Campbell (University of Aberdeen, UK), this series will consider articles that report on any topic relevant to the role, definition and use of the pragmatic trial design.

Doug Altman

About the Editors

Doug Altman, Editor-in-Chief

Doug Altman graduated in statistics from the University of Bath and has worked for the Medical Research Council as a statistical consultant in a wide variety of medical areas. In 1988 he became head of the newly formed Medical Statistics Laboratory (now Medical Statistics Group) at ICRF (now Cancer Research UK), and in 1995 also became founding director of the Centre for Statistics in Medicine in Oxford. In 1997, Professor Altman received the Bradford Hill Medal for his contributions to medical statistics and a DSc from the University of London, and in 1998 was made Professor of Statistics in Medicine by the University of Oxford. His varied research interests include the use and abuse of statistics in medical research, studies of prognosis, regression modelling, systematic reviews and meta-analysis, randomised trials, and studies of medical measurement.

Jeremy Grimshaw

Jeremy Grimshaw, Editor-in-Chief

Jeremy Grimshaw is a Senior Scientist in the Clinical Epidemiology Program at the Ottawa Health Research Institute and Professor of Medicine, University of Ottawa. He holds a Tier 1 Canadian Research Chair in health knowledge transfer and uptake. Professor Grimshaw’s research interests are in implementation and knowledge translation, quality improvement, complex interventions, systematic reviews, cluster randomized trials, quasi-experimental studies and behavioral theories (and their application to professional behavior).

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Tianjing Li, Editor-in-Chief

Tianjing Li is an Associate Professor in the Department of Epidemiology at Johns Hopkins Bloomberg School of Public Health (JHBSPH). Dr Li was trained as a physician and subsequently earned her PhD in Epidemiology (Clinical Trials concentration) and MHS in Biostatistics from JHBSPH. The primary goal of Dr Li's research is to develop, evaluate, and disseminate efficient methods for comparing healthcare interventions and to provide trustworthy evidence for decision making. Her core research interests include methodologies for randomized controlled trials, systematic reviews, network meta-analysis, comparative effectiveness research, and patient-centered outcomes research. Dr Li serves as the Associate Director for Cochrane United States and the Director for Research for Cochrane Eyes and Vision US Project.

Celebrating Trials' 10th anniversary

2016 marked the 10th anniversary of Trials and to coincide with publication of our 3000th article, we put together a page to celebrate the great milestones of the journal, including a timeline, opinions from those in the field, links to our most popular articles, and more.


2016 Journal Metrics