Data statements in publications signpost where data directly supporting the publication can be found and under what conditions it can be accessed.
The University of Liverpool Research Data Management policy also states that publications should include a statement.
The UKRI policy on publishing your research findings states that published results should always include information about how to access the supporting data. If the data cannot be shared openly, there should still be metadata that is available and discoverable indicating under what conditions data can be shared.
Supplementary files are not a substitute for sharing datasets via a repository and unless published open access, in most cases copyright rests with the publisher.
When data has been deposited in a trusted research data repository, you simply link to the digital object identifier (DOI) of that dataset in a brief statement. If the publisher does not have a specific field in the submission process then the statement should appear on your final draft at the bottom near acknowledgements.
You need the DOI of your dataset before your publication is published, at the latest in the final submission of the paper after acceptance.
Statements for alternative scenarios should be used as appropriate indicating that:
- There is no additional data
- The data is available via the supplementary files (not ideal)
- Data sharing available under certain circumstances, stating the circumstances or linking to a record that does.
- The data is unavailable to due to ethical or other reasons
If your research is the secondary analysis of datasets, you should reference these or advise that all are cited appropriately within the article. Always cite existing datasets that you have used.
The University of Bath has some good examples of data statements.