Article Text

Download PDFPDF

Has open data arrived at the British Medical Journal (BMJ)? An observational study
  1. Anisa Rowhani-Farid,
  2. Adrian G Barnett
  1. Australian Centre for Health Services Innovation (AusHSI), Institute of Health and Biomedical Innovation (IHBI), Queensland University of Technology (QUT), Brisbane, Queensland, Australia
  1. Correspondence to Anisa Rowhani-Farid; anisa.rowhanifarid{at}


Objective To quantify data sharing trends and data sharing policy compliance at the British Medical Journal (BMJ) by analysing the rate of data sharing practices, and investigate attitudes and examine barriers towards data sharing.

Design Observational study.

Setting The BMJ research archive.

Participants 160 randomly sampled BMJ research articles from 2009 to 2015, excluding meta-analysis and systematic reviews.

Main outcome measures Percentages of research articles that indicated the availability of their raw data sets in their data sharing statements, and those that easily made their data sets available on request.

Results 3 articles contained the data in the article. 50 out of 157 (32%) remaining articles indicated the availability of their data sets. 12 used publicly available data and the remaining 38 were sent email requests to access their data sets. Only 1 publicly available data set could be accessed and only 6 out of 38 shared their data via email. So only 7/157 research articles shared their data sets, 4.5% (95% CI 1.8% to 9%). For 21 clinical trials bound by the BMJ data sharing policy, the per cent shared was 24% (8% to 47%).

Conclusions Despite the BMJ's strong data sharing policy, sharing rates are low. Possible explanations for low data sharing rates could be: the wording of the BMJ data sharing policy, which leaves room for individual interpretation and possible loopholes; that our email requests ended up in researchers spam folders; and that researchers are not rewarded for sharing their data. It might be time for a more effective data sharing policy and better incentives for health and medical researchers to share their data.

  • Data Sharing
  • Open Data
  • Open Science
  • Research Integrity
  • Reproducibility

This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) license, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited. See:

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.


  • Twitter Follow Anisa Rowhani-Farid at @AnisaFarid and Adrian Barnett at @aidybarnett

  • Contributors AR-F was involved in data collection, data analysis, writing of manuscript. AGB was involved in data verification, design of study and student supervision, editing of manuscript, statistical code for data analysis. Both authors had full access to all of the data (including statistical reports and tables) in the study and can take responsibility for the integrity of the data and the accuracy of the data analysis.

  • Funding This project is supported in kind by the Australian Centre for Health Services Innovation which is based at the Institute of Health and Biomedical Innovation at Queensland University of Technology (QUT) in Brisbane, Australia.

  • Competing interests None declared.

  • Ethics approval This study received low-risk ethical approval from the Office of Research Ethics and Integrity at QUT.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data sharing statement The data set (with all identifiers removed) is deposited as a data supplement at the Dryad data repository at with the doi:10.5061/dryad.q8s5k. The data is free for re-use by all other researchers and there are no additional forms or ethics applications that need to be completed.