Metadata policy

This policy covers all the statistical data that the Office for National Statistics (ONS) holds either as a data controller or a data processor, including those obtained through surveys and from administrative sources in the private or public sectors. The policy is valid from data acquisition and collection by the ONS, and it also extends through the lifecycle up to and including data archiving and data disposal.

This policy applies to all UK Statistics Authority and ONS employees, including staff on fixed-term, temporary or permanent contract, staff on secondment, students and contractors.

Metadata provide information about other data, including a description of the data. This includes information that provides context to the data (for example, how it was collected), or the coverage of the data (for example, publication date, description and search keywords).

The ONS needs to hold and manage a comprehensive set of unambiguous metadata relating to the data it manages, in order to understand the data, fully extract the value from the data and employ appropriate security measures to protect the data.

The ONS Data Strategy specifies data principles for managing data; data policies support the implementation of these principles. This metadata policy aligns with the data principles and underpins the management and governance of metadata in the ONS. The metadata must comply with the data principles.

Metadata provide information about other data and are essential in aiding understanding of the data and ensuring that appropriate security measures are employed to protect the data. Metadata will be defined and centrally maintained for all data held by the ONS from acquisition to dissemination, archiving and disposal.

All data acquired and collected by the ONS from external and internal sources must be accompanied by metadata. The ONS Metadata Model defines the minimum set of metadata that must accompany all data acquired by the ONS. In practice, captured metadata will go beyond the defined minimum set of metadata. In order to provide a framework for managing metadata, metadata categories have been defined and all metadata will be categorised according to these categories.

ONS Information assets held on the Information and Data Asset Register will be assigned a Metadata Owner, in addition to the Information Asset Owner. The Metadata Owner will periodically review the quality of the metadata they own and will initiate corrective action to address any issues found with the accuracy and quality of the metadata.

The ONS Business Glossary holds definitions for the main terms used within the ONS. Glossary Term Owners are appointed at the time of data acquisition, creation or amendment, and are responsible for maintaining their terms, updating and consolidating them with other terms as appropriate.

1.    Metadata will be defined and centrally maintained for all data held by the ONS from acquisition to archiving and disposal:

• data acquired and collected by the ONS from external and internal sources must be accompanied by metadata; the metadata must contain at least a minimum set of metadata elements that are shared across the ONS data estate
• data provided by the ONS to external recipients must be accompanied by metadata; this metadata must be up-to-date managed metadata
• new data created by the ONS (for example, statistical outputs, including internally created new variables and datasets) must be accompanied by metadata
• data held in ONS-managed data archives must be accompanied by metadata
• metadata will be retained for data that has been deleted (disposed of), including the date of deletion
• metadata will be retained for the appropriate period specified by the retention policy

2.    The metadata will be categorised according to the defined ONS Metadata Categories and the recorded metadata attributes will align with the ONS Metadata data model.

3.    Information about Metadata Owners will be recorded on the Information and Data Asset Register:

• the Metadata Owner will periodically review the quality of the metadata they own and will initiate corrective action to address any issues found with the accuracy and quality of the metadata
• the Metadata Owner will assign a retention period for the metadata according to the retention policy

4.    Metadata will comprise a consistent set of minimum metadata elements as defined by the ONS Metadata data model:

• the minimum set of metadata will include descriptive, structural and administrative metadata
• both the Information Asset Owner and the Metadata Owner will ensure that their assets are described by at least the set of minimum metadata elements and will ensure that they are recorded in the appropriate data catalogue

5.    The Business Glossary will be updated with new terms, or the definition of existing terms will be consolidated at the time of data acquisition, creation or amendment:

• the Glossary Term Owners will be appointed at the time of data acquisition, creation or amendment
• term owners will ensure that their terms are up-to-date, linked to other terms, consolidated and deleted if appropriate

Metadata Owner 

The Metadata Owner will be responsible for:

• ensuring the details of the metadata that they own are correct and of high completeness and are managed in accordance with the metadata retention period they have defined
• initiating corrective action to address any issues found with the availability, accuracy and completeness of the metadata
• liaising with the data experts and metadata experts in the data controller organisation (the ONS or external data controller) to ensure that the metadata attached to a dataset meet the analytical and governance requirements and comply with all relevant standards

Lead Data Architect

The Lead Data Architect is accountable to the Chief Data Architect and is responsible for:

• informing Metadata Owners of any changes (implemented by the Data Architecture Team) to this policy and to related data principles, data standards and guidance
• ensuring a communication plan is implemented to inform interested parties (for example, those who are involved in acquiring, creating or amending data and metadata), what their responsibilities are and what processes should be followed to ensure that metadata is managed throughout the lifecycle

Data Curators:

• whoever acquires or creates new data must ensure that the corresponding metadata is collected or defined; the metadata must comply with data standards, particularly with the data standards that specify the minimum set of metadata that needs to be provided

• whoever amends existing data must ensure that the corresponding metadata is amended or kept up-to-date and that the Metadata Owner is informed of the changes

• whenever new data is acquired or created, a Metadata Owner must be assigned

• whoever acquires or creates new data or amends existing data must check whether the Business Glossary needs to be updated and ensure the relevant changes are implemented in a timely fashion

Glossary Term Owners:

• Glossary Term Owners maintain a set of terms in the ONS Business Glossary; the term owners will assign Subject Matter Experts for their terms
• the term owners will be responsible for maintaining, updating, consolidating and linking terms to others in the Business Glossary as necessary according to ONS Business Glossary workflows and approval procedures