Overview

The FReSH metadata schema defines the structure and constraints of metadata used by the FReSH metadata catalog.

The schema specifies:

• Metadata fields and their semantics
• Data types and allowed values
• Cardinality and mandatory/optional constraints

Schema Structure

The FReSH metadata schema is organized into a series of thematic sections.
Each section groups metadata fields that describe a specific aspect of a resource in the FReSH catalog and is documented in a dedicated file.

Sections

1. Technical metadata
   Defines the technical characteristics of the metadata record itself, including identifiers, schema versions and machine-readable properties necessary for processing and validation.
2. Study related information
   Describes the study or resource at a conceptual level, including titles, abstracts, keywords, thematic classifications and high-level contextual information.
3. Administrative information
   Covers aspects related to governance and accountability, such as creators, publishers, contacts, roles and administrative metadata necessary for catalog management.
4. Study methodology
   Documents the methodological aspects of the study, including design, methods, instruments and other information necessary to understand how the data was produced.
5. Data collection and access
   Describes how data was collected, stored and made available, including access conditions, formats, distributions and licensing information.

Cardinality and Data Types

Cardinality is expressed using standard conventions:

• 1 – exactly one value (mandatory)
• 0..1 – zero or one value (optional)
• 0..n – zero or more values
• 1..n – one or more values

Data types follow commonly adopted definitions (e.g. string, boolean, date, URI) and may reference external standards if necessary.