Deposition of Open Metadata
L. Waltman 
History
| Version | Revision date | Revision | Author |
|---|---|---|---|
| 1.0 | 2023-05-21 | Initial draft | L. Waltman |
Description
Scientific publications have metadata that describes important properties of the publication, such as the title, the authors, the publication date, and the references. This metadata is used to help researchers and others find relevant literature. Metadata of publications is also often used in bibliometric analyses to support research evaluation and research management.
Traditionally the metadata of scientific publications is made available in proprietary commercial databases. However, the importance of openness of this metadata is increasingly recognized, as shown for instance by the Initiative for Open Citations and the Initiative for Open Abstracts.
Our focus is on openness of the metadata of research articles. We acknowledge the importance of openness of other types of publications, such as books, book chapters, and policy reports. Nevertheless, in most scientific fields, research articles are seen as the most important publication type, and we therefore restrict ourselves to this publication type.
Metrics
Journal articles with Open References
This metric provides the number or the percentage of journal articles for which the references are openly available.
Measurement.
Crossref is the datasource for this metric. Crossref makes the references of articles openly available, but it can do this only for articles for which the publisher submitted the references to Crossref. The metric is obtained by determining for each article whether it has a Crossref DOI and whether the metadata for this DOI includes references.
If the metadata of an article in Crossref does not include references, this means that either the publisher did not submit the references to Crossref or the article does not have any references. There is no straightforward way to distinguish between these two possibilities.
The Crossref Participation Reports provide this metric at the level of publishers and journals. The metric is also used in this article on Open Metadata in Crossref. To calculate the metric yourself, you may use the Crossref API, documented at https://api.crossref.org/swagger-ui/index.html. The references-count field in the API output indicates whether the metadata of an article includes references.
Journal articles with Open Abstracts
This metric provides the number or the percentage of journal articles for which the abstract is openly available.
Measurement.
Crossref is the datasource for this metric. Crossref makes the abstracts of articles openly available, but it can do this only for articles for which the publisher submitted the abstract to Crossref. The metric is obtained by determining for each article whether it has a Crossref DOI and whether the metadata for this DOI includes an abstract.
If the metadata of an article in Crossref does not include an abstract, this means that either the publisher did not submit the abstract to Crossref or the article does not have an abstract. There is no straightforward way to distinguish between these two possibilities.
The Crossref Participation Reports provide this metric at the level of publishers and journals. The metric is also used in this article on Open Metadata in Crossref. To calculate the metric yourself, you may use the Crossref API, documented at https://api.crossref.org/swagger-ui/index.html. If the metadata of an article includes an abstract, it can be found in the abstract field in the API output.
Journal articles with Open Funding Information
This metric provides the number or the percentage of journal articles for which funding information is openly available.
Measurement.
Crossref is the datasource for this metric. Crossref makes funding information of articles openly available, but it can do this only for articles for which the publisher submitted funding information to Crossref. The metric is obtained by determining for each article whether it has a Crossref DOI and whether the metadata for this DOI includes funding information.
If the metadata of an article in Crossref does not include funding information, this means that either the publisher did not submit funding information to Crossref or the article does not include any funding information. There is no straightforward way to distinguish between these two possibilities.
The Crossref Participation Reports provide this metric at the level of publishers and journals. The metric is also used in this article on Open Metadata in Crossref. To calculate the metric yourself, you may use the Crossref API, documented at https://api.crossref.org/swagger-ui/index.html. If the metadata of an article includes funding information, this information can be found in the funder field in the API output.