The Significance of Clinical Data Sharing

In a growing consensus, many foundations, government agencies, and industries around the world now mandate clinical data sharing.

Reputable medical journals act as platforms that bring clinical trial data together and facilitate data sharing through the International Committee of Medical Journal Editors (ICMJE). This small working group of general medical journal editors believes that there is an ethical obligation to responsibly share data generated by interventional clinical trials because participants have put themselves at risk.

ICMJE participants meet annually and fund their own work on the Recommendations for the Conduct, Reporting, Editing and Publication of Scholarly Work in Medical Journals.

US-based members of the ICMJE include the Annals of Internal Medicine, Journal of the American Medical Association, New England Journal of Medicine, PLOS Medicine, and the National Library of Medicine.

The ICMJE instills individual patient data sharing obligations and seeks to share de-identified individual patient data underlying the results presented in articles (including tables, figures, and appendices or supplementary material) no later than 6 months after their publication.

As a condition of consideration for publication in member journals, authors are required to include a description of the data-sharing plan in the submitted manuscript. This requirement aims in part to prevent selective publication and reporting of research outcomes, as well as unnecessary duplication of research efforts.

Prospective trial registration currently includes documenting the planned primary and major secondary endpoints that will be assessed in order to enable identification of incomplete reporting as well as post-hoc analyses. Declaring a plan for sharing data prior to their collection further enhances transparency in the conduct and reporting of clinical trials by exposing whenever data availability after trial completion differs from prior commitments.

ICMJE editors do not consider the deposition of data in a registry to constitute prior publication.

Authors of secondary analyses using shared data must also attest that the use was in accordance with the terms (if any) agreed to upon their receipt. Referencing the source of the data using a unique identifier of a clinical trial’s dataset is also required to provide appropriate credit to those who generated it and enabling searching for the studies it has supported.

Authors of secondary analyses must explain completely how their datasets differ from previous analyses. In addition, those who generate and then share clinical trial datasets deserve substantial credit for their efforts.

Those using data collected by others should seek collaboration with those who originally collected the data. However, because collaboration will not always be possible, practical, or desired, an alternative means of providing appropriate credit needs to be developed and recognized in the academic community.

Clinical data sharing is a shared responsibility. Editors of individual journals can help foster data sharing by changing the requirements of the manuscripts they will consider for publication in their journals, but funders and sponsors of clinical trials are in a position to support and ensure adherence to individual patient data sharing obligations.

If journal editors become aware that individual patient data sharing obligations are not being met, they may choose to request additional information; publish an expression of concern; notify the sponsors, funders, or institutions; or, in certain cases, retract the publication.

Sharing data will increase confidence and trust in the conclusions drawn from clinical trials. It will enable the independent confirmation of results—an essential tenet of the scientific process—and it will foster the development and testing of new hypotheses.

When done well, clinical trial data sharing can glean the most key learnings from each trial and avoid unwarranted repetition. The ICMJE believes this will benefit patients, investigators, sponsors, and society.