What is it?

Controlled vocabularies are systematically organised lists of standardised terms, codes and definitions used to describe, index and classify data. They play a key role in the data management ecosystem by ensuring the unambiguous interpretation of concepts. By using controlled vocabularies, ambiguities that arise from the use of free text are avoided, enabling information systems to communicate more effectively with one another and helping users find the information they need more accurately.

These vocabularies are a cornerstone of the FAIR data principles (Findability, Accessibility, Interoperability and Reusability). In Lithuania, multilingual vocabularies are being developed in cooperation with international partners such as CESSDA ERIC and the DDI Alliance. This means that terms are linked to their equivalents in other languages. Such an approach allows a user to submit a query in Lithuanian and retrieve results from international databases, even when the original data are described in English, French or German.

How to use it?

Controlled vocabularies are recommended when creating data metadata, that is, when describing datasets. Instead of manually entering characteristics such as data collection frequency, unit of analysis or software used, users should select values from approved lists. This improves data quality and visibility in international catalogues, such as the European Data Portal.

Relevant vocabularies can be viewed and downloaded through specialised platforms such as the CESSDA ERIC Vocabulary Services. These platforms provide the latest versions, which can be integrated into information systems. Terms are presented together with unique identifiers, definitions and translations.

If you are a data user, these vocabularies can help you understand specific codes in data files and formulate more precise search queries when using data catalogues.