Metadata coverage and completeness of OJS journals in Crossref

Public availability of good quality metadata (including persistent identifiers) for diamond journals is important for increasing journal visibility, especially in bibliographic databases beyond Scopus and Web of Science. In turn, visibility facilitates inclusion of articles in diamond journals in research assessment and evaluation processes. Journals registering DOIs with Crossref can deposit metadata for articles, including authors, affiliations, abstracts, funding, licenses and references. These metadata are then made publicly available in machine-readable form, and are used by aggregators and bibliographic databases like OpenAlex, OpenAIRE and GoTRIPLE. We evaluated the coverage and completeness of various metadata types for current OJS journals that use Crossref, leveraging open metadata from Crossref and the dataset provided by PKP on publications using OJS software There generally is good coverage of abstracts and licenses for OJS journals in Crossref, but metadata on authors (including ORCIDs), affiliations, funding and references are only deposited by a minority of journals. These data can be further broken down by journal and publisher size and by OJS version, providing empirical evidence for factors correlated with deposition of metadata. Together with concrete examples of good practices at journal and publisher level, this information can help in capacity building of diamond journal publishing, supporting publishers to deposit more complete metadata. In addition, this analysis provides a concrete use case for research using and combining open data sources, and how this can contribute to community-led publishing and other developments in scholarly communication. The datasets used in this analysis are made available through Google Big Query allowing both verification and further analysis, including longitudinal monitoring of metadata coverage and completeness of OJS journals.