Authorship contributions statement

What a contributions statement is

A contributions statement moves beyond the author byline — which shows only who is named — to explain what each person did. In its simplest form it is a list: "A.B.: Conceptualization, Methodology; C.D.: Data curation, Formal analysis; E.F.: Writing — original draft; all authors: Writing — review and editing." In its most structured form it is captured as linked metadata, associating each contribution with an ORCID iD and a standardised role identifier.

The practice grew from the contributorship model proposed in a 1997 JAMA editorial, which argued that the author byline was an unreliable signal of who actually did what. Journals initially collected free-text contribution paragraphs; the move to a controlled vocabulary came with the development of CRediT.

The CRediT taxonomy

The Contributor Roles Taxonomy (CRediT) defines 14 roles covering the full research lifecycle: Conceptualization, Methodology, Software, Validation, Formal analysis, Investigation, Resources, Data curation, Writing — original draft, Writing — review and editing, Visualization, Supervision, Project administration, and Funding acquisition. Each role can be qualified as lead, equal or supporting. CRediT was originated by CASRAI in 2014 in collaboration with publishers and research funders, and is now standardised as ANSI/NISO Z39.104-2022 by NISO (available at credit.niso.org). It is the de facto standard for author contribution statements across Elsevier, Springer Nature, Wiley and many other publishers.

How to write a contributions statement

List each author with the CRediT roles they performed, using the standardised role names. Where roles were shared, include all relevant authors under the role. Where a role was not applicable, omit it rather than leaving a blank. Journals may provide a template or a submission-system interface that renders the statement automatically.

For example: "Initials A: Conceptualization, Methodology, Supervision. Initials B: Investigation, Data curation, Formal analysis, Writing — original draft. Initials C: Resources, Funding acquisition. All authors contributed to Writing — review and editing and approved the final version."

Journal requirements and vs acknowledgements

Contributions statements differ from acknowledgements. Acknowledgements recognise contributions that do not meet authorship criteria — laboratory support, funding bodies, editorial help. A contributions statement covers the named authors' specific roles. Some journals and publishers (including Elsevier journals using the CRediT author statement form) require a CRediT statement for all submissions; others request it; a growing number make it mandatory. Authors should check the target journal's instructions for authors for the exact format required.