Thema: Graham Bell describes Thema, the new subject classification for the global book industry

“Subject classification of books lies at the heart of discoverability, improved sales, borrowing and market intelligence. Describing what books are about – in a consistent and controlled manner – is critical for publishers, booksellers, libraries and readers. For readers, subject classification drives physical shelving schemes and online ‘browse by subject’. For booksellers and libraries, subject data is used to ensure the right mix of products is available to the customer and borrower.

“reduced duplication of work”

But there are so many different subject schemes. The potential value of a single, global classification scheme is clear: it lies in reduced duplication of work where more than one scheme is in use, in the elimination of costly and imprecise mapping processes, and in avoiding the loss of precision that’s inevitable in such mappings. A global scheme also enables international market research, comparisons and benchmarking, and this value grows with the increasingly international nature of the book trade.

Thema is a new subject scheme that aims to be global in scope, multicultural and multi-lingual, while remaining highly practical – it’s far simpler than library-focused schemes like UDC. It’s applicable to all parts of the book supply chain, and is flexible enough to allow each market to retain its unique cultural voice, while remaining a unified and simple-to-adopt standard. Initially, it can be used alongside the existing national schemes, but has the potential eventually to replace them.

” far simpler than library-focused schemes like UDC.”

Since Thema grew from the original BIC subject scheme, it looks and works a lot like BIC. But close up, there are some very significant differences: Thema has incorporated ideas and experience from a number of other established national subject schemes. It lays out a hierarchy of subjects: 20 top level categories, each subdivided into many sub-categories, and each having a heading (e.g. Geological surface processes (geomorphology)), an alpha-numeric code (e.g. RBGD) and, in some cases, associated notes. There are around 2,500 subject headings in total. In addition, post-coordinated ‘qualifiers’ can be used to refine the meaning of the main categories with geographical, historical or stylistic nuances. For anyone used to BIC, this is seemingly familiar stuff, but there are significant differences of emphasis, and uniquely, Thema has a mechanism to add country-specific extensions to the qualifiers too.

Although most of the Thema headings are defined originally in English, the scheme is available in multiple languages – so the subject code MKE is labelled ‘dentistry’, ‘Zahnheilkunde’, ‘odontología’ and طب الأسنان and so on. The codes are language-independent, so metadata that includes Thema categorisations is highly portable. Since launch, a dozen translations have been completed and others are under way.

“Thema is free of charge for anyone to use”

Thema is managed by EDItEUR, the international trade standards body for the book trade. This puts it under the same roof as ONIX, EDItX and other metadata, identifier and e-commerce standards. And like those other EDItEUR standards, Thema is free of charge for anyone to use. Although EDItEUR’s work on Thema and its other standards is funded through membership fees (and new members are always very welcome), there is no requirement for membership. This is possible because BIC and Nielsen have kindly donated the relevant intellectual property (derived from the original BIC scheme) to EDItEUR.”

Graham Bell, Executive Director of EDItEUR

Graham Bell is Executive Director of EDItEUR. Graham previously worked for HarperCollins Publishers in the UK, where most recently he was Head of Publishing Systems. He led the development of bibliographic and digital asset management systems, and was involved with the launches of many HarperCollins digital initiatives including e-audio, e-books and print-on-demand programmes. He has over a decade of experience with ONIX for Books. Prior to HarperCollins, he worked as an editor and in IT roles within the magazine industry with Redwood Publishing and BBC Magazines.

For Thema details, see the EDItEUR website or the interactive browser .