Extended definition
A data availability statement (DAS) is the formal section of an article that reports whether and how the data underlying the work can be accessed: deposited in a repository with a persistent identifier, included in supplementary material, available on request to the author, or unavailable for ethical, legal, or contractual reasons. The DAS is the instrument that operationalizes the FAIR principles at the level of the individual article, turning the abstract expectation of findable and accessible data into a verifiable declaration. Journals and funders adopted it widely over the past decade; PLOS, for instance, has required a DAS since 2014. Federer and colleagues (2018) analyzed the statements of nearly 48,000 PLOS ONE articles and showed that, although the presence of a DAS grew, only about 20% indicated deposit in a repository, the form of sharing the journal’s policy defines as preferred. The DAS is therefore not a bureaucratic detail: it is the point where an openness policy meets the author’s concrete practice.
When it applies
The DAS applies whenever a journal or funder requires it, and nearly every high-impact venue now does. It applies with greatest force when data can be shared without restriction: there, the robust form is deposit in a recognized repository, with a persistent identifier and an explicit license, cited in the statement itself. It also applies as an element of transparency that supports reanalysis, evidence synthesis, and independent verification of results. In clinical studies and in research funded by public agencies, the DAS is part of the implicit accountability contract: reader, reviewer, and funder use it to judge whether a finding is auditable. Filled out well, it reduces research waste by letting others reuse the data rather than recollect it.
When it does not apply
The DAS does not guarantee that the data exist, are correct, or are in fact accessible. The “available on reasonable request” formula is the instrument’s blind spot: Gabelica and colleagues (2022) contacted authors who had declared this willingness and obtained usable data in fewer than 7% of cases, a rate indistinguishable from articles with no DAS at all. Tedersoo and colleagues (2021) reached the same conclusion across disciplines and recommended that journals stop accepting availability-on-request statements. The DAS also does not apply as a universal mandate for full openness: sensitive data, third-party records, and qualitative material may not be shareable for ethical or privacy reasons; in those cases the DAS documents and justifies the restriction, rather than feigning a sharing that will not happen.
Applications by field
- Biomedicine and health: a growing requirement in clinical journals; the tension between transparency and patient-data protection makes the DAS the place to declare controlled access.
- Life sciences and genomics: deposit in disciplinary repositories (GenBank, ENA, PRIDE) with the accession number cited directly in the statement.
- Social sciences and humanities: more cautious use; qualitative and identifiable data lead to justified restricted-access statements, not open deposit.
- Computing and data science: joint declaration of data and code in repositories such as Zenodo or OSF, with a persistent identifier and a reuse license.
Common pitfalls
The first pitfall is the “on request” statement, which the evidence shows is, in practice, a promise rarely kept. The second is conflating supplementary material with a repository: attaching spreadsheets to the article secures neither findability, persistence, nor reuse, which are the point of the DAS. The third is declaring availability without a persistent identifier, leaving the data on a personal-page link that expires. The fourth is omitting the license: data without an explicit license is legally ambiguous and, in practice, not reusable. The fifth is treating the DAS as a submission formality, filled with whatever sounds acceptable to pass review, rather than a commitment the author intends to honor.