Subject Authority: avoiding the unknown unknown

We recently had a query from a user who asked us to explain the value of SCIS Subject Headings and the ScOT vocabulary — and the rather tricky subject of authority control. This query often comes up in our inbox, at conferences and at professional learning sessions, so now feels like a good time for a blog post on the matter.

SCIS vs ScOT — which to choose?
Firstly, we do not consider this an either/or scenario; nor do 100% of our users. SCIS Subject Headings have been developed and refined to support best-practice for resource management in education. SCIS records provide the foundation of consistent, best-quality metadata, to which ScOT headings can be a valuable supplement.

The SCIS Subject Headings vocabulary dates back to the early 1980s and is a pre-coordinated subject headings list. It is intended as an educationally-focused alternative to the Library of Congress Subject Headings. SCIS subscribers can choose to supplement SCIS Subject Headings with ScOT, a post-coordinated vocabulary of topical headings.

ScOT is a freely available vocabulary, owned and managed by Education Services Australia; ScOT is also used to tag the Australian Curriculum. One of the major benefits of utilising SCIS data is that users can choose to include ScOT headings in their library records. Without a SCIS subscription, the application of ScOT headings on a title-by-title basis would be extremely time-consuming, undoing the value of the SCIS centralised cataloguing model that school librarians have benefited from for over 30 years.

What happens if I don’t want ScOT terms in my catalogue?
If you manually download records from the SCIS website, you have the option of adjusting your profile setting to have both SCIS and ScOT terms, or SCIS headings only.  Please note this profile setting does not apply to records downloaded via the z39.50 protocol. The option to switch off ScOT terms via z-cataloguing is dependent on the Library Management System you use, and we recommend contacting your vendor for further advice.

What are SCIS Authority Files?
SCIS Authority Files improve search and discovery in the library catalogue. With Authority Files, SCIS data can be linked across records, to display the ‘See’ and ‘See also’ references. When a student enters a search term, all relevant results will be returned. Users can then make their search broad, or narrow.

Authority Files include:

  • An authorised list of names and subject headings; for example, author names.
  • A reference structure to link authorised terms to related terms, providing guidance to improve information literacy skills.
  • Direction from alternative (non-preferred) terms to authoritative terms; for example, the subject heading ‘cyclone’ is linked to the alternative term ‘hurricane’.

You can watch our video on SCIS Authority Files here.

What are the implications if I don’t use SCIS Subject Headings and Authorities?
The decision not to use SCIS Subject Headings and SCIS Authority Files is unlikely to be noticed by library patrons. The impact of poor authority control is insidious and, by its nature, people do not notice it. It results in a slow degradation of the quality and comprehensiveness of search results. People do not notice it because they don’t know about what they aren’t finding… it is an ‘unknown unknown’.

In 2015, SCIS published an article that discussed the value of keeping subject headings clean. The article gave an example of the SCIS Subject Heading ‘Excursions’ and the American Library of Congress (LOC) heading ‘School field trips’. If your catalogue included some records with the SCIS heading and other records with the LOC heading, then searching on either heading would not return the records containing the other headings. In information science jargon, this is an example of poor recall — the number of retrieved results is less than the total relevant results.

We recently reviewed a publicly accessible school library catalogue that has stopped using SCIS Subject Headings to determine the impact. A subject search for items with the heading ‘Excursions’ found 18 results published in 2016. A search using the heading ‘School field trips’ found 38 results published in 2016. Only seven items were in both sets. This is an example of the poor recall that can be attributed to losing control of subject authorities.

SCIS believes that the precise and considered practice of authority control will only become more important as libraries move to replace textual values with linked-data identifiers, and SCIS will be at the forefront of that practice. We consider authority control integral to best-practice resource management, and we are looking forward to releasing our new SCIS series authority in mid-2018.

What’s next for SCIS?
SCIS Subject Headings and SCIS Authority Files are designed to save cataloguing time and improve resource discoverability within a library. These are some of many benefits that explain why SCIS has a large and loyal customer base and a growing international clientele.

SCIS recognises that many in the library industry are eager to learn more about our roadmap for SCIS development and enhanced metadata. We recently released our new website, and more improvements are on their way. To keep up with the latest news on SCIS, please keep an eye on Connections and our various social media channels: Facebook , Twitter and LinkedIn.

Further reading
Kneebone, L 2015, ‘The relationship between SCIS Subject Headings and ScOT’, Connections, no. 95,

SCIS 2016, ‘SCISSHL and ScOT: why use both?’, SCIS blog, 9 May,

Styles, J 2015, ‘From the desk of a cataloguer’, Connections, no. 94,

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Rachel is General Manager at Education Services Australia, loves SCIS, and has a professional interest in content curation and advocacy.

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