Intended for healthcare professionals

CCBYNC Open access
Research Methods & Reporting

Preparing raw clinical data for publication: guidance for journal editors, authors, and peer reviewers

BMJ 2010; 340 doi: (Published 29 January 2010) Cite this as: BMJ 2010;340:c181
  1. Iain Hrynaszkiewicz, managing editor1,
  2. Melissa L Norton, editorial director (medicine)1,
  3. Andrew J Vickers, associate attending research methodologist2,
  4. Douglas G Altman, professor of statistics in medicine3
  1. 1BioMed Central, 236 Gray’s Inn Road, London WC1X 8HL
  2. 2Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, NY, NY 10021, USA
  3. 3Centre for Statistics in Medicine, University of Oxford, Wolfson College Annexe, Oxford OX2 6UD
  1. Correspondence to: I Hrynaszkiewicz iain.hrynaszkiewicz{at}
  • Accepted 11 December 2009

Many peer reviewed journals now require authors to be prepared to share their raw, unprocessed data with other scientists or state the availability of raw data in published articles, but little information on how such data should be prepared for sharing has emerged. Iain Hrynaszkiewicz and colleagues propose a minimum standard for de-identifying datasets to ensure patient privacy when sharing clinical research data

Summary points

  • Despite journal and funder policies requiring data sharing, there has been little practical guidance on how data should be shared

  • Confidentiality and anonymity are key considerations when publishing or sharing data relating to individuals, and this article provides practical advice on data sharing while minimising risks to patient privacy

  • Consent for publication of appropriately anonymised raw data should ideally be sought from participants in clinical research

  • Direct identifiers such as patients’ names should be removed from datasets; datasets that contain three or more indirect identifiers, such as age or sex, should be reviewed by an independent researcher or ethics committee before being submitted for publication


Many peer-reviewed journals’ instructions for authors require that authors should be prepared to share their raw (that is, unprocessed) data with other scientists on request. Although data sharing is commonplace in some scientific disciplines and is a requirement of a number of major research funding agencies’ policies, this culture has not yet been widely adopted by the clinical research community. Some journals have appealed to their authors to increase the availability of medical research data,1 2 3 recognising the benefits of such transparency. These benefits are well documented and include replication of previous findings, comparisons with independent datasets, testing of additional hypotheses, teaching, and patient safety.3 4 5 6 Moreover, patients themselves are increasingly seeing the benefits of openly sharing their experiences with others (

Online journals with unlimited …

View Full Text