Subject codes, incomplete and unreliable, have got to go | Crossref

by Patrick Polischuk

Subject classifications have been available via the REST API for many years but have not been complete or reliable from the start and will soon be deprecated. dfdfd

The subject metadata element was born out of a Labs experiment intended to enrich the metadata returned via Crossref Metadata Search with All Subject Journal Classification codes from Scopus. This feature was developed when the REST API was still fairly new, and we now recognize that the initial implementation worked its way into the service prematurely.

While subject classifications in Crossref metadata could be very useful, the current implementation in the REST API is problematic for three primary reasons:

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Where does that leave us? Rather than continuing to supply unreliable and misleading subject category metadata, we will be deprecating this feature in the coming weeks. To minimize disruption and avoid breaking changes at this time, we will be removing this data from our index, so the subject element will simply be empty. We may remove the subject element in the future.